Accepted Cycle 11 Observing Proposals

SN, SNR & ISOLATED NS

Proposal Number	Subject Category	PI Name	Title
11500004	SN, SNR AND ISOLATED NS	Pavlov	Young, hot PSR J1357-6429 and its PWN
11500011	SN, SNR AND ISOLATED NS	Kaastra	Monitoring the spectral evolution of RXJ0720-3125 and determining its nature
11500021	SN, SNR AND ISOLATED NS	Predehl	HFPK 334: A New Supernova Remnant in the Small Magellanic Cloud
11500027	SN, SNR AND ISOLATED NS	Garmire	X-ray emission from the old pulsar B1451-68
11500032	SN, SNR AND ISOLATED NS	Garmire	SNR RCW 103: Ejecta, Blast Wave, and the Central Compact Object
11500036	SN, SNR AND ISOLATED NS	Murray	Completing the Timing of Two Isolated Neutron Stars
11500041	SN, SNR AND ISOLATED NS	Murray	Imaging Supernova Remnant 1987A at the Highest Resolution
11500043	SN, SNR AND ISOLATED NS	Garmire	Search for Long GRB Jet Breaks
11500043	SN, SNR AND ISOLATED NS	Garmire	Search for Long GRB Jet Breaks
11500044	SN, SNR AND ISOLATED NS	Garmire	Snap-shot survey of unidentified galactic GeV sources
11500065	SN, SNR AND ISOLATED NS	KATSUDA	The First X-Ray Expansion Measurements of the Cygnus Loop
11500068	SN, SNR AND ISOLATED NS	Burrows	CHANDRA CYCLE 11 SPATIAL AND SPECTRAL MONITORING OF SNR1987A
11500078	SN, SNR AND ISOLATED NS	Safi-Harb	Probing the Central Engine of the Plerionic SNR CTB 87
11500201	SN, SNR AND ISOLATED NS	Petre	A Direct X-Ray Expansion Measurement of the SMC SNR 1E 0102.2--7219
11500222	SN, SNR AND ISOLATED NS	Lorimer	PSRJ1832+0029: a unique target for pulsar emission physics
11500272	SN, SNR AND ISOLATED NS	PARK	A Detailed Study of the Aged O-Rich Supernova Remnant 0049-73.6
11500276	SN, SNR AND ISOLATED NS	PARK	A Detailed Study of the Type Ia Supernova Remnant G299.2-2.9
11500355	SN, SNR AND ISOLATED NS	Bernardini	Unveiling the nature of cyclic behavior in the period evolution of the Anomalous X ray Pulsar XTE j1810-197
11500373	SN, SNR AND ISOLATED NS	Chiang	THE X-RAY EVOLUTION OF SUPERNOVA 2004AM
11500374	SN, SNR AND ISOLATED NS	Berger	Rapid Observations of Short Gamma-Ray Bursts: Accurate Positions Hold the Key to the Progenitor Population
11500395	SN, SNR AND ISOLATED NS	Kouveliotou	TOO Observations of Soft Gamma Repeaters
11500430	SN, SNR AND ISOLATED NS	Chandra	Solving the mystery of Type IIn supernovae
11500452	SN, SNR AND ISOLATED NS	Roberts	A Search for X-Rays From Pulsars Discovered by Fermi
11500474	SN, SNR AND ISOLATED NS	Soderberg	The Energetics and Environments of 'Naked' Supernovae
11500485	SN, SNR AND ISOLATED NS	Kaspi	Target-of-Opportunity Chandra Observations of Glitching High-B Radio Pulsars: Searching for Magnetar Metamorphoses
11500488	SN, SNR AND ISOLATED NS	Soderberg	An In-Depth Study of the Nearest Gamma-Ray Bursts
11500493	SN, SNR AND ISOLATED NS	Kaspi	TINY HICCUPS TO TITANIC EXPLOSIONS: Tackling Transients in Anomalous X-ray Pulsars
11500524	SN, SNR AND ISOLATED NS	Pooley	Catching up to the Hydrogen Envelope: Late-time X-ray Observations of Type Ib/c SNe
11500537	SN, SNR AND ISOLATED NS	Tanaka	Chandra Observation of a Gamma-ray Emitting SNR, W44
11500541	SN, SNR AND ISOLATED NS	Terrier	Investigating the nature of the candidate SNR G29.37+0.10
11500573	SN, SNR AND ISOLATED NS	Gotthelf	Two Magnetar Candidates in HESS Supernova Remnants
11500575	SN, SNR AND ISOLATED NS	Weisskopf	Search for the X-Ray counterpart to LAT PSR J2021+4026
11500674	SN, SNR AND ISOLATED NS	Pooley	Chandra Observations of New X-ray Supernovae
11500703	SN, SNR AND ISOLATED NS	De Luca	A DEEP CHANDRA/NOAO INVESTIGATION TO IDENTIFY THE COUNTERPART OF AN OLD PULSAR DISCOVERED IN GAMMA-RAYS
11500712	SN, SNR AND ISOLATED NS	Delaney	The Proper Motion of the Central Compact Object in Cassiopeia A
11500714	SN, SNR AND ISOLATED NS	Hughes	The Proper Motion of SNR E0519-69.0
11500744	SN, SNR AND ISOLATED NS	Butler	Nailing Down the Broadband Properties of a Short GRB with the help of Chandra
11500770	SN, SNR AND ISOLATED NS	Gavriil	Chandra Monitoring of the Rotation-Powered Pulsar/Magnetar Transition Object PSR J1846-0258
11500788	SN, SNR AND ISOLATED NS	McLaughlin	Crab Giant Pulses: A Correlation Study at Radio and X-rays
11500799	SN, SNR AND ISOLATED NS	Rol	Constraining GRB phycis through their afterglow light curves
11500803	SN, SNR AND ISOLATED NS	Patnaude	Testing Shock Physics Through Flux Variability in Cas A
11500804	SN, SNR AND ISOLATED NS	Hui	Confirming and exploring the supernova remnant candidate G308.3-1.4
11500846	SN, SNR AND ISOLATED NS	Bauer	Tracking the X-ray Evolution of the Enigmatic SN1996cr
11500865	SN, SNR AND ISOLATED NS	Kargalstev	The long tail of PSR J1740+1000
11500877	SN, SNR AND ISOLATED NS	Sivakoff	Constraining the Distance & Temperature of LAT PSR J1742-20, The Newly Discovered Nearby Middle-Aged Neutron Star

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500004

Title: Young, hot PSR J1357-6429 and its PWN

PI Name: George Pavlov

Observations of thermal components in the X-ray spectra of young pulsars provide insights into fundamental physics of neutron star interiors and magnetospheres. A short XMM-Newton exposure of the 7 kyr old PSR J1357-6429 has revealed thermal emission from the NS surface and an elongated diffuse feature extending from the pulsar, most likely a pulsar wind nebula (PWN). Observations with Chandra HRC-S have have provided tentative detections of a compact PWN and pulsations. Here we propose a detailed study of the pulsar's spectral and timing properties, and deep imaging and spectroscopy of the PWN with XMM-Newton and Chandra.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:57:02.40	-64:29:30.20	PSR J1357-6429	ACIS-I	NONE	60

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500011

Title: Monitoring the spectral evolution of RXJ0720-3125 and determining its nature

PI Name: Jelle Kaastra

RX J0720.4-3125 belongs to a group of radio-quiet isolated neutron stars, whose spectra are characterized by a blackbody spectrum plus one or more broad absorption features. It is unique in that its blackbody temperature, and the depth of the absorption feature is variable. The cause for this spectral evolution is unclear, but one proposed model is free precession of a neutron star with two hot spots. However, the exact precession period, if it exists, is not well known, but must be of the order of 10 yr. Alternatively, an unknown cause may have heated the atmosphere or changed the magnetic field configuration. In that case one may expect that at some point the source changes back to the situation before 2003.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
07:20:25.00	-31:25:50.20	RX J0720-3125	HRC-S	LETG	35

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500021

Title: HFPK 334: A New Supernova Remnant in the Small Magellanic Cloud

PI Name: Peter Predehl

XMM-Newton observations of selected fields in the SMC revealed a new SNR outside of the major star forming regions where most other SNRs are found. Radio data confirm the SNR nature of the object and the 20 cm radio image reveals an extent of about one arcmin in diameter. Most of the radio emission originates from at least 5 blobs which are about 10 arcsec in diameter. A comparison of the X-ray and radio images indicates that a similar morphology might also be present in the X-ray image, with softer emission originating from the outer radio lobes. The morphology of HFPK 334 might suggest that there is a central source associated with the SNR shell. We propose a Chandra observation to resolve the X-ray emission from the SNR to investigate the possible presence of a pulsar wind nebula.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:03:28.00	-72:47:30.00	HFPK 334	ACIS-S	NONE	28.5

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500027

Title: X-ray emission from the old pulsar B1451-68

PI Name: Gordon Garmire

X-ray observations of old radio pulsars are needed for studying their evolution and the mechanisms of their magnetospheric and thermal emission. To expand the current small sample of old pulsars observed in X-rays, we propose an ACIS-S observation of the 42 Myr old pulsar B1451-68.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:56:00.20	-68:43:39.00	PSR B1451-68	ACIS-S	NONE	35

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500032

Title: SNR RCW 103: Ejecta, Blast Wave, and the Central Compact Object

PI Name: Gordon Garmire

Supernova Remnant (SNR) RCW 103 is a young Type II SNR showing bright X-ray shell and the peculiar central compact object (CCO). While the bright X-ray shell appears to be the shocked stellar winds produced by the massive progenitor, other characteristic features for a young Type II SNR such as metal-rich ejecta and the outer blast wave have not been detected. We propose an 80 ks ACIS observation to search for these features. We will also perform spectral and temporal study of the CCO.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:17:37.60	-51:01:13.00	RCW 103	ACIS-I	NONE	80

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500036

Title: Completing the Timing of Two Isolated Neutron Stars

PI Name: Steve Murray

The nearest thermally emitting neutron stars offer some of the clearest clues to the true demography of neutron stars, and arguably the best prospects for measuring neutron-star radii. For both tasks, knowledge of their magnetic field strengths is essential, and hence we have been determining timing solutions with Chandra and XMM. The results show a surprisingly tight grouping of magnetic field strengths in a range intermediate between normal pulsars and magnetars, with a hint at an interaction between the thermal emission and magnetic field. For the two sources observed most recently, however, our analysis is limited by the time-span and gaps in the data. We request one short observations of each of those two sources to achieve much more accurate timing solutions.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
21:43:03.30	+06:54:17.00	RX J2143.0+0654	ACIS-S	NONE	12
08:06:23.40	-41:22:30.90	RX J0806.4-4123	ACIS-S	NONE	18

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500041

Title: Imaging Supernova Remnant 1987A at the Highest Resolution

PI Name: Steve Murray

HRC observations of SN 1987A have revealed the detailed morphology of the remnant, allowing robust measurements of the size and other geometric parameters. We propose a second epoch HRC observation which will indicate the source evolution. The results will be combined with ACIS and radio data to serve as inputs to our hydrodynamic simulations, with the aim to determine the structure of the underlying circumstellar material. We note that the proposed HRC observation will complement rather than conflict with any ACIS observations of SN 1987A, since ACIS data carry spectral information, while HRC data have superior spatial resolution.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:35:28.00	-69:16:11.20	SN 1987A	HRC-I	NONE	35

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500043

Title: Search for Long GRB Jet Breaks

PI Name: Gordon Garmire

In the standard fireball model for GRB afterglows, the jet opening angle can be determined from the achromatic jet break time by measuring the time at which this break in the light curve occurs. Swift XRT observations have shown that jet breaks are not observed in the first several days or weeks of a typical X-ray afterglow. This has important implications for the derived energetics of the GRB itself that cannot be resolved without a more complete sample of observed jet breaks. We propose to follow 4 carefully chosen long GRB afterglows with late-time Chandra observations in order to search for jet breaks occurring after the Swift observations end.

Target Name	Det.	Grating	Exp.Time
GRB AO11-01	ACIS-S	NONE	60
GRB AO11-02	ACIS-S	NONE	60
GRB AO11-03	ACIS-S	NONE	60
GRB AO11-04	ACIS-S	NONE	60

Target Name	Det.	Grating	Exp.Time
GRB AO11-01	ACIS-S	NONE	60
GRB AO11-02	ACIS-S	NONE	60
GRB AO11-03	ACIS-S	NONE	60
GRB AO11-04	ACIS-S	NONE	60

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500044

Title: Snap-shot survey of unidentified galactic GeV sources

PI Name: Gordon Garmire

We will observe unidentified GeV sources in the Galactic plane recently discovered by Fremi/LAT. Most of the galactic GeV sources are likely to be associated with pulsars and SNRs. High-resolution X-ray observations provide an efficient way to identify the nature of GeV sources and obtain a much more complete census of galactic neutron stars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:18:15.00	-58:58:41.00	0FGL J1018.2-5858	ACIS-I	NONE	10
18:44:23.00	-03:30:29.00	0FGL J1844.1-0335	ACIS-I	NONE	10
14:30:35.00	-59:20:18.90	0FGL J1430.5-5918	ACIS-I	NONE	10
14:13:10.00	-62:03:47.00	0FGL J1413.1-6203	ACIS-I	NONE	10
18:21:28.00	-14:44:24.00	0FGL J1821.4-1444	ACIS-I	NONE	10
16:48:07.00	-46:06:43.00	0FGL J1648.1-4606	ACIS-I	NONE	10
17:41:25.00	-30:46:23.00	0FGL J1741.4-3046	ACIS-I	NONE	10

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500065

Title: The First X-Ray Expansion Measurements of the Cygnus Loop

PI Name: SATORU KATSUDA

We propose to perform a second-epoch observation of the northeastern limb of the Cygnus Loop supernova remnant to measure its expansion. The edges of the X-ray emission are associated with Balmer-dominated filaments whose proper motions were recently measured to be 0".09/yr. Assuming that the proper motion of the Balmer-dominated filament is equal to that of the edge of the X-ray--emitting plasma, we expect to see a shift of 0".72 between the first- and the second-epoch Chandra observations. We can directly compare proper motions between optical and X-rays, for the first time. The comparison will provide key information on the origin of the X-ray--emitting plasma in the Cygnus Loop. We request one pointing observation with an exposure time of 40ksec.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:54:38.80	+32:16:27.90	Cygnus Loop NE Rim re-visited	ACIS-S	NONE	40

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500068

Title: CHANDRA CYCLE 11 SPATIAL AND SPECTRAL MONITORING OF SNR1987A

PI Name: David Burrows

Regular monitoring of SNR1987A, the only supernova remnant in which we can study the early developmental stages in detail, is critical to testing models of remnant evolution, nonequilibrium ionization processes, and thin plasma spectra. SNR1987A presents a unique opportunity to observe the birth and early evolution of a supernova remnant at high spatial and spectral resolution for the first time. We propose to continue our program of monitoring SNR1987A in Cycle 11 at roughly six month intervals.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:35:28.00	-69:16:11.10	SNR 1987A	ACIS-S	HETG	64
05:35:28.00	-69:16:11.10	SNR 1987A	ACIS-S	HETG	59

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500078

Title: Probing the Central Engine of the Plerionic SNR CTB 87

PI Name: Samar Safi-Harb

Pulsar wind nebulae (or plerions) are an ideal laboratory to study the physics of neutron stars and particle acceleration; and Chandra is the ideal satellite to probe their powering engines and image their X-ray emission with an unprecedented resolution. Among the plerionic SNRs, nearly a dozen have properties that differ from the Crab nebula, and are therefore dubbed as plerions of the `second kind'. We propose to explore CTB 87, the least studied member of this class in X-rays, in order to study the putative pulsar and perform a high-resolution imaging and spectroscopic study of the plerion, including the search for structures associated with the deposition of the neutron star's energy into its surroundings.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:16:09.10	+37:11:10.20	CTB 87	ACIS-I	NONE	70

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500201

Title: A Direct X-Ray Expansion Measurement of the SMC SNR 1E 0102.2--7219

PI Name: Robert Petre

We propose to make the first direct X-ray proper motion measurement of an extragalactic SNR, 1E~0102.2-7219 in the SMC. Its proper motion was indirectly measured in 2000 using a combination of Einstein, ROSAT, and Chandra data to be 0.1 \%/yr. The corresponding fast shock velocity implies a higher postshock proton temperature than can be consistent with the spectrally measured electron temperature behind the forward shock unless a significant fraction of the shock energy is diverted from heating the gas, most likely to particle acceleration. A direct measurement of the shock velocity using Chandra will confirm this important result. Duplicating an early 20 ks HRC observation provides a 10 year baseline, allowing four independent proper motion measurements around the forward shock.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:04:02.40	-72:01:55.30	1E 0102.2-7219	HRC-I	NONE	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500222

Title: PSRJ1832+0029: a unique target for pulsar emission physics

PI Name: Duncan Lorimer

We have discovered very unusual behavior in PSR J1832+0029, a 533-ms radio pulsar which switches between on and off states on timescales of several hundred days. Remarkably, the pulsar's spin-down rate almost doubles when the radio emission is on. This is even more dramatic than observed for PSR B1931+24 for which no satisfactory theory presently exists. Unlike PSR B1931+24, J1832+0029 is nearby (1.3 kpc) and an excellent target for X-ray detection. Here we request a 20 ks ACIS TOO to study the X-ray emission of PSR J1832+0029 in its off state, triggered by radio monitoring. Together with our recent GO observation, this TOO will help distinguish between radio emission quenching mechanisms that are either intrinsic to the pulsar or caused by accretion from an orbiting companion.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:32:50.80	+00:29:27.20	PSR J1832+0029	ACIS-S	NONE	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500272

Title: A Detailed Study of the Aged O-Rich Supernova Remnant 0049-73.6

PI Name: SANGWOOK PARK

O-rich supernova remnants (SNRs) provide an excellent opportunity for the study of core-collapse (CC) nucleosynthesis and the late-stage evolution of a massive star. While young O-rich SNRs (e.g., Cas A and G292.0+1.8) are being extensively studied, such studies are intrinsically limited because the early-stage of the blast wave and reverse shock may not reveal the full nature of metal-rich ejecta and the surroundings. Studies of relatively old O-rich SNRs are essential for a comprehensive understanding of CC SNRs, complementing those of young SNRs. The old O-rich SNR 0049-73.6 is a perfect example for such a study, revealing both high- and low-Z ejecta and well-evolved blast wave. Thus, we propose a deep 450 ks ACIS observation of 0049-73.6 for a detailed X-ray imaging spectroscopy.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
00:51:07.00	-73:21:30.00	SNR 0049-73.6	ACIS-S	NONE	450

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500276

Title: A Detailed Study of the Type Ia Supernova Remnant G299.2-2.9

PI Name: SANGWOOK PARK

Supernova remnant (SNR) G299.2-2.9 is a unique example of the Type Ia SNR which allows us a detailed 2-D spectral study for both of the metal-rich ejecta and ambient structures. Such studies of the ejecta and ambient medium are essential to reveal the detailed SNe Ia explosion mechanisms and their specific environments, which would critically impact their utility in cosmology. The proposed studies of both of the Type Ia SN ejecta and ambient structures cannot be performed with young historical Type Ia SNRs, and the mid-aged Type Ia SNR G299.2-2.9 provides a unique opportunity. Thus, we propose a 640 ks Chandra observation of G299.2-2.9. The proposed observation will serve a legacy which will be an essential basis for a high resolution spectroscopy of Type Ia SNRs with IXO and Astro-H.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
12:14:50.00	-65:28:25.00	G299.2-2.9	ACIS-I	NONE	640

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500355

Title: Unveiling the nature of cyclic behavior in the period evolution of the Anomalous X ray Pulsar XTE j1810-197

PI Name: Federico Bernardini

This program is aimed at obtaining a phase coherent time solution for the period evolution of XTEJ1810-197 (XTE),and concluding the successful X-ray monitoring of this unique Anomalous X-ray Pulsar (AXP),the first identified transient AXP,a neutron star (NS) whose emission is due to the decay of an extremely high magnetic field (10e15 G).Its transient behavior,outburst flux increase ~100,allowed us to monitor its time properties for 6 years.The source was found to be a bright and highly polarized transient radio pulsar.Important new informations on AXP have been gathered from simultaneous X-ray and radio band observations.The pointings we request are aimed at checking for the presence of precession of its rotation axis.XTE could be the unique precessing AXP(there are only 3 precessing NS)

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:09:51.10	-19:43:51.90	XTE J1810-197	ACIS-S	NONE	25
18:09:51.10	-19:43:51.90	XTE J1810-197	ACIS-S	NONE	25

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500373

Title: THE X-RAY EVOLUTION OF SUPERNOVA 2004AM

PI Name: Yi-Kuan Chiang

Recently, we found a new candidate of an X-ray supernova (XSN), SN 2004am, that shows rising X-ray flux for several years after explosion. There are only two SNe, SN 1996cr and SN 1987A, which have similar long-term X-ray light curve. If SN 2004am is similar to the other two Type II SNe, the supergiant progenitor likely explodes into a wind-blown bubble resulting a unique X-ray light curve. Further regular monitoring observations of SN 2004am will allow us to constrain the light curve slope and luminosity. By comparing these with SN 1996cr and SN 1987A, we might be able to gain valuable information about the circumstellar matter density structure. Hence, confirming the XSN nature of SN 2004am will add an important sample in studying late-time behaviors of Type II SNe.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
09:55:46.60	+69:40:38.10	SN 2004am	ACIS-S	NONE	10

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500374

Title: Rapid Observations of Short Gamma-Ray Bursts: Accurate Positions Hold the Key to the Progenitor Population

PI Name: Edo Berger

Only 1/4 of all short GRBs are localized to sub-arcsecond accuracy, required for unambiguous host and redshift identifications, determination of the burst environment (disk, bulge, halo, IGM), and assessment of natal kicks. These properties determine the identity and ages of the progenitors, and the GRB explosion properties. Thus, much of our knowledge depends on a handful of events, which are moreover biased to high density environments by virtue of optical/UV/radio detections. Here we propose to double the fraction of events with sub-arcsecond positions, and overcome the density bias, using rapid Chandra observations of bursts with only Swift/XRT positions (3-6"). Swift data will guarantee Chandra detections at <4 days, and follow-up work will delineate the burst/host properties.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		Short-GRB-1	ACIS-S	NONE	20
		Short-grb-2	ACIS-S	NONE	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500395

Title: TOO Observations of Soft Gamma Repeaters

PI Name: Chryssa Kouveliotou

Soft Gamma Repeaters are rare sources of transient burst emission, probably magnetars (i.e. strongly magnetized neutron stars). Each of the SGRs has a persistent X-ray counterpart and some show coherent pulsations. During burst active phases, these counterparts undergo changes in their energy spectrum and pulse properties. Measuring the effects of burst activity are diagnostic of the burst mechanism and SGRs in general. In the event of detection of substantial burst activity from an SGR, we propose to make Chandra ToO observations of any of the six known sources, SGR 1900+14, SGR 1806-20, SGR 1550-5418, SGR 0501+4516, SGR 1627-41, SGR 0526-66, the SGR candidate SGR 1801-23, as well as any newly discovered SGR source.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
19:07:14.30	+09:19:20.10	SGR 1900+14	ACIS-S	NONE	40
18:08:39.30	-20:24:39.50	SGR 1806-20	ACIS-S	NONE	40
16:35:51.80	-47:35:23.30	SGR 1627-41	ACIS-S	NONE	40
05:26:01.10	-66:04:38.00	SGR 0526-66	ACIS-S	NONE	40
05:01:06.80	+45:16:33.90	SGR 0501+4516	ACIS-S	NONE	40
15:50:54.10	-54:18:23.80	SGR 1547-5408	ACIS-S	NONE	40
18:00:58.90	-22:56:48.50	SGR 1801-23	ACIS-S	NONE	40
		NEW SGR	ACIS-S	NONE	40
19:07:14.30	+09:19:20.10	SGR 1900+14	ACIS-S	NONE	25
18:08:39.30	-20:24:39.50	SGR 1806-20	ACIS-S	NONE	25
16:35:51.80	-47:35:23.30	SGR 1627-41	ACIS-S	NONE	25
05:26:01.10	-66:04:38.00	SGR 0526-66	ACIS-S	NONE	25
05:01:06.80	+45:16:33.90	SGR 0501+4516	ACIS-S	NONE	25
15:50:54.10	-54:18:23.80	SGR 1547-5408	ACIS-S	NONE	25
18:00:58.90	-22:56:48.50	SGR 1801-23	HRC-I	NONE	15

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500430

Title: Solving the mystery of Type IIn supernovae

PI Name: Poonam Chandra

X-ray observations of young supernovae provide unique constraints on the circumstellar density, profile, and elemental composition of the ejecta. Fingerprinting the exploded ejecta composition through X-ray spectroscopy can give clues to the mass and progenitor mass loss history of the exploding star. Both of these will help in understanding the relation of Type IIn progenitors to those of other classes of supernovae.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		Type IIn SN	ACIS-S	NONE	40

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500452

Title: A Search for X-Rays From Pulsars Discovered by Fermi

PI Name: Mallory Roberts

The Fermi LAT has discovered 14 gamma-ray pulsars that had not been previously detected as pulsars at other wavelengths. Many of these have relatively low spin down energies, suggesting they are nearby. Here we request Chandra ACIS imaging observations of three of these pulsars in order to search for X-ray counterparts in order to obtain accurate positions for timing and follow-up optical studies, search for extended emission from a compact pulsar wind nebulae, and make preliminary spectral and flux measurements.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
06:33:44.00	+06:32:24.80	PSR J0633+06	ACIS-S	NONE	20
19:07:51.70	+06:01:19.20	PSR J1907+06	ACIS-S	NONE	20
17:32:50.80	-31:35:17.90	PSR J1732-31	ACIS-S	NONE	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500474

Title: The Energetics and Environments of 'Naked' Supernovae

PI Name: Alicia Soderberg

Twenty years have passed since the peculiar class of Type Ibc supernovae were recognized as core-collapse explosions. However, it is only recently that SNe Ibc have enjoyed a surge of interest thanks to their association with GRBs. Today, the most crucial questions is whether SNe Ibc and GRBs arise from similar or distinct progenitor systems. Progress requires a detailed study of ordinary SNe Ibc which out-number GRBs by a factor of 100. Here we propose a focused program that leverages CXO data with those from Swift/XRT and the Very Large Array.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		SNIbc1	ACIS-S	NONE	10
		SNIbc2	ACIS-S	NONE	10

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500485

Title: Target-of-Opportunity Chandra Observations of Glitching High-B Radio Pulsars: Searching for Magnetar Metamorphoses

PI Name: Victoria Kaspi

We recently discovered a high-magnetic-field rotation-powered pulsar undergoing a "magnetar metamorphosis" simultaneously with a rotation glitch, transforming from an ordinary rotation-powered pulsar into a much brighter X-ray source with very different spectrum, and even possibly impacting on its nebular surroundings. After <8 weeks, the source returned to its normal state. This amazing event, caught serendipitously, suggests that all high-magnetic-field radio pulsars undergo such transient metamorphoses at glitch epochs, but have not been so recognized because of the absence of a sensitive all-sky monitor. We therefore request Chandra ToO observations of one high-magnetic-field radio pulsar when it has a large glitch in order to test this hypothesis.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
01:57:49.90	+62:12:25.90	PSR B0154+61	ACIS-S	NONE	105
07:26:08.10	-26:12:38.10	PSR J0726-2612	ACIS-S	NONE	105
08:47:57.00	-43:16:57.20	PSR J0847-4316	ACIS-S	NONE	105
10:01:32.20	-59:39:17.80	PSR J1001-5939	ACIS-S	NONE	105
11:19:14.30	-61:27:49.50	PSR J1119-6127	ACIS-S	NONE	105
16:32:39.70	-48:18:52.60	PSR J1632-4818	ACIS-S	NONE	105
17:18:10.00	-37:18:53.00	PSR J1718-3718	ACIS-S	NONE	105
17:26:07.50	-35:29:58.00	PSR J1726-3530	ACIS-S	NONE	105
17:34:26.60	-33:33:22.00	PSR J1734-3333	ACIS-S	NONE	105
18:14:43.10	-17:44:48.00	PSR J1814-1744	ACIS-S	NONE	105
18:19:33.80	-14:58:01.00	PSR J1819-1458	ACIS-S	NONE	105
18:21:34.30	-14:19:26.00	PSR 1821-1419	ACIS-S	NONE	105
18:47:35.20	-01:30:46.00	PSR J1847-0130	ACIS-S	NONE	105
19:13:50.80	+04:46:06.00	PSR J1913+0446	ACIS-S	NONE	105
19:18:23.60	+14:45:06.00	PSR B1916+14	ACIS-S	NONE	105
		New High-B pulsar	ACIS-S	NONE	105

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500488

Title: An In-Depth Study of the Nearest Gamma-Ray Bursts

PI Name: Alicia Soderberg

Just a decade ago, astronomers thought stellar core-collapse was primarily a spherical process. Gamma-ray bursts, with collimated jets (powered by a central engine) and at the same time a spherical explosion (supernova) have upset this paradigm. Empirically there appears to be a wide range in the energy of the explosion. This opens up the possibility that "jet-driven" explosions are common for all supernovae. Here we propose an in-depth study of the nearest gamma-ray bursts. Our synergistic multi-wavelength effort (radio, optical, Swift/XRT and proposed CXO) are designed to extract the true energy of these explosions.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		low-z GRB	ACIS-S	NONE	45

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500493

Title: TINY HICCUPS TO TITANIC EXPLOSIONS: Tackling Transients in Anomalous X-ray Pulsars

PI Name: Victoria Kaspi

The past decade has seen major progress in neutron star astrophysics, with the discovery of magnetars in general, and the recognition that the Anomalous X-ray Pulsars (AXPs) fall in this class. AXPs have recently revealed surprising and dramatic variability behavior, which theorists have begun to show are highly constraining of physical models of magnetars, including their crusts, atmospheres, coronae and magnetospheres. In this proposal, we request Chandra/ACIS-S Target-of-Opportunity observations of one major Anomalous X-ray Pulsar (AXP) outburst in A11, in order to study in detail the evolution of the spectrum, pulsed fraction and pulse profile, for quantitative confrontation with recently developed models for the structure and electrodynamics of magnetars.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
10:50:08.90	-59:53:20.40	1E 1048.1-5937	ACIS-S	NONE	90
23:01:07.90	+58:52:46.00	1E 2259+586	ACIS-S	NONE	90
17:08:47.20	-40:08:50.70	RXS 1708-4009	ACIS-S	NONE	90
01:46:22.30	+61:45:07.00	4U 0142+61	ACIS-S	NONE	90
18:41:19.20	-04:56:12.50	1E 1841-045	ACIS-S	NONE	90
18:44:53.00	-02:56:40.00	AX J1845-0258	ACIS-S	NONE	90
01:00:43.10	-72:11:33.80	CXOU J0110043.1-721134	ACIS-S	NONE	90
18:09:51.10	-19:43:51.70	XTE J1810-197	ACIS-S	NONE	90
16:47:10.20	-45:52:17.00	CXOU J164710.2-455216	ACIS-S	NONE	90
		New AXP	ACIS-S	NONE	90
15:50:55.30	-54:19:02.00	1E 1547.0-5408	ACIS-S	NONE	90
18:46:24.50	-02:58:28.00	J1846-0258	ACIS-S	NONE	90

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500524

Title: Catching up to the Hydrogen Envelope: Late-time X-ray Observations of Type Ib/c SNe

PI Name: David Pooley

We propose Chandra observations of five Type Ib/c supernovae (SNe) which show signs of strong, late-time circumstellar (CSM) interaction, a fascinating new phenomenon discovered by our team. Exploring this transition from modest CSM interaction typical of Type Ib/c SNe to strong CSM interaction typical of Type IIn SNe will allow us to probe the transition of the progenitor star from its pre-Wolf-Rayet phase into the Wolf-Rayet phase and learn details about how its hydrogen envelope was shed. This is a new and unique opportunity, and Chandra observations are the best way of pursuing it.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
16:21:48.90	-02:16:17.30	SN 2004dk	ACIS-S	NONE	8
21:42:23.70	+12:29:50.90	SN 2001em	ACIS-S	NONE	10
06:16:16.20	-21:22:09.80	SN 1999ec	ACIS-S	NONE	13
14:22:22.70	-00:23:24.30	SN 1996aq	ACIS-S	NONE	7
23:04:54.90	+12:18:20.10	SN 1990U	ACIS-S	NONE	25

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500537

Title: Chandra Observation of a Gamma-ray Emitting SNR, W44

PI Name: Takaaki Tanaka

We propose to study a mixed-morphology SNR W44, where a gamma-ray source was detected in a close vicinity by EGRET. Recent observations by Fermi have revealed that position and morphology of the gamma-ray source is similar to those of radio and IR, suggesting that the gamma-rays are of hadronic origin and originate in shocked molecular clouds. We propose here to observe the northern part of the SNR, from which Fermi detected strong gamma-ray emission. This is the first on-axis observation of this region by Chandra, which enables us to study the X-ray morphology of the gamma-ray emitting region with the superb angular resolution. Our aim is to detect non-thermal emission (presumably proton or electron bremsstrahlung) and to constrain the emission model for the gamma-ray emission.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:55:34.10	+01:33:04.00	W44 North	ACIS-I	NONE	60

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500541

Title: Investigating the nature of the candidate SNR G29.37+0.10

PI Name: Regis Terrier

The new supernova remnant (SNR) candidate G29.37+0.10 is a very peculiar object: a bright jet or filament-like structure lying at the centre of a faint radio shell. The nature of the jet structure is unclear. Originally interpreted as a radio Galaxy, the association with a shell SNR is also suggesting a pulsar wind nebula (PWN) or microquasar system. Two X-ray point sources and a hint of diffuse emission are detected on the edge of the northeastern radio lobe in archival data, one of them being variable. Recently HESS has discovered a large complex of TeV emission, HESS J1843-033, the north eastern wing of which is coincident with G29.37+0.10. We propose a deep Chandra observation to determine the origin of the high energy particles and the actual nature of this unusual SNR candidate.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:44:42.50	-03:05:36.00	G29.37+0.10	ACIS-I	NONE	60

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500573

Title: Two Magnetar Candidates in HESS Supernova Remnants

PI Name: Eric Gotthelf

We have identified two new candidate magnetars in HESS detected shell-type SNRs. The X-ray point sources have AXP-like spectra, and periods in the magnetar range. We propose a second timing observation of each object in order to infer its magnetic field strength and spin-down power. This will potentially double the number of magnetar/SNR associations in the Galaxy, and address whether an early evolutionary stage of a magnetar can contribute to diffuse TeV emission, a heretofore unknown channel.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:14:05.70	-38:10:30.90	CXOU J171405.7-381033	ACIS-S	NONE	30
17:32:03.30	-34:45:17.70	XMM J173203.3-344518	ACIS-S	NONE	40

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500575

Title: Search for the X-Ray counterpart to LAT PSR J2021+4026

PI Name: Martin Weisskopf

We propose a Chandra ACIS-S imaging observation of the pulsating gamma-ray source LAT PSR J2021+4026. This is the 5th brightest source in the gamma-ray sky and the brightest source lacking a counterpart at all other wavelengths from radio to X-rays. The full Fermi/LAT 99-percent error circle will be imaged on S3. This gives the optimum throughput and highest sensitivity for the expected soft thermal spectrum plus power-law. Extensive followup optical and radio observations will be performed independently.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
20:21:31.00	+40:26:46.00	FERMI-LAT PSR J2021+4026	ACIS-S	NONE	60

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500674

Title: Chandra Observations of New X-ray Supernovae

PI Name: David Pooley

We propose to continue our X-ray studies of Type II and Type Ib/c supernovae (SNe). The Swift satellite has ushered in a new era of studying SNe in the X-rays, obtaining densely sampled X-ray lightcurves for the first time. However, its spatial resolution is often not good enough to separate a SN from nearby sources. We propose short Chandra observations to alleviate this. These observations will assess the X-ray environment of newly discovered Swift SNe to determine any possible source confusion or contamination of the SN flux. Our strategy makes the best use of the capabilities of each observatory.

Target Name	Det.	Grating	Exp.Time
SN 2	ACIS-S	NONE	10
SN 3	ACIS-S	NONE	10
SN 4	ACIS-S	NONE	10

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500703

Title: A DEEP CHANDRA/NOAO INVESTIGATION TO IDENTIFY THE COUNTERPART OF AN OLD PULSAR DISCOVERED IN GAMMA-RAYS

PI Name: Andrea De Luca

After 5 months of all-sky scanning, the Fermi Large Area Telescope (LAT) has discovered 15 new gamma-ray pulsars using a blind search algorithm. The discovery of a population of radio-quiet (or at least radio-faint), bright gamma-ray pulsars has deep implications for gamma-ray source population studies, as well as for our overall understanding of pulsar physics. We propose a multiwavelength project within the frame of Chandra/NOAO joint observations, aimed at identifying the X-ray counterpart of one of the most exciting members of the newly discovered pulsar sample: a bright gamma-ray pulsar with timing properties pointing to an old neutron star with a very low rotational energy loss. Possibly very close to us, such pulsar is a factor 10 less energetic and significantly older than Geminga

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
03:57:50.50	+32:05:26.20	LAT PSR J0357+32	ACIS-S	NONE	80

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500712

Title: The Proper Motion of the Central Compact Object in Cassiopeia A

PI Name: Tracey Delaney

We propose to measure the proper motion of the central compact object (CCO) in Cassiopeia A over a 10-year baseline. The CCO is an enigma that does not fit cleanly into any compact object category. It is offset from the optical expansion center of the supernova remnant which suggests a proper motion of 350 km/s in a direction perpendicular to the well-known northeast-southwest jet axis. However, the actual proper motion is NOT KNOWN and may not be tied to the offset direction at all. The true direction and magnitude of the CCO's proper motion can be used to provide constraints on its nature and the dynamics of core-collapse supernovae.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:23:25.80	+58:48:53.40	Cassiopeia A	HRC-I	NONE	50

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500714

Title: The Proper Motion of SNR E0519-69.0

PI Name: John Hughes

We propose to measure independently the proper motion expansions of the ejecta and forward shock in SNR E0519-69.0. The metal-enriched reverse-shock-heated ejecta emits only in X-rays, while the forward shock is traced to high precision by H alpha emission. The proposed measurements require the unique high resolution imaging capabilities of Chandra and Hubble. The optical (forward shock) and X-ray (ejecta) results will yield important constraints on the remnant's evolutionary state; we will search in particular for evidence of cosmic-ray modified dynamics. An important component of this project is an integrated theoretical investigation using realistic models of SN Ia explosions evolved to the remnant stage.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:19:35.00	-69:02:10.00	SNR E0519-69.0	ACIS-S	NONE	52

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500744

Title: Nailing Down the Broadband Properties of a Short GRB with the help of Chandra

PI Name: Nathaniel Butler

Understanding of the origin and nature of short/hard Gamma-ray bursts (SHBs) is one of the last frontiers of GRB research. We propose a 3 epoch ToO observations of one SHB, as part of a broadband followup campaign. We hope to decisively answer the following questions: Do the afterglows of SHBs arise from external shocks? What are the explosion energy, external density, and micro-physical parameters? In what environments do SHBs occur, galaxy clusters? Are the afterglows isotropic, and what is the SHB rate? What drives the X-ray flaring, which apparently occurs many dynamical timescales after a putative compact object merger?

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		Short /hard GRB	ACIS-S	NONE	50

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500770

Title: Chandra Monitoring of the Rotation-Powered Pulsar/Magnetar Transition Object PSR J1846-0258

PI Name: Fotis Gavriil

The young pulsar PSR J1846-0258 was long thought to be exclusively rotation-powered. Our discovery of magnetar-like emission from this source makes it the only known example of a rotation-powered pulsar/magnetar transition object. Following its outburst, our Rossi X-ray Timing Explorer (RXTE) observations revealed that the pulsar's pulsed flux returned to its quiescent value. However, with our background dominated RXTE observations we cannot determine whether the spectrum and total flux, and hence pulsed fraction, have as well. PSR J1846-0258 is the only source that exhibits both magnetar-like emission and a bright and variable pulsar wind nebula (PWN). The requested observations will help constrain the nature of the interesting variability observed in this PWN.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
18:46:24.90	-02:58:30.10	PSR J1846-0258	ACIS-S	NONE	52

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500788

Title: Crab Giant Pulses: A Correlation Study at Radio and X-rays

PI Name: Maura McLaughlin

We request an 20-ks observation of the Crab pulsar with the Chandra HRC-S to correlate radio giant pulses with X-ray photons. The goal of our experiment is to obtain the best constraints ever on the giant pulse emission mechanism. We will accumulate about 20,000 radio giant pulses with simultaneous Chandra data, making this the first such correlation study at these energies to date. This work is important for constraining the giant-pulse emission mechanism and for testing the first quantitative model for radio giant pulses. It will also help us to understand the elusive pulsar emission mechanism in general and probe the exotic physics of relativistic particle acceleration in high magnetic fields.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
05:34:32.00	+22:00:52.10	PSR B0531+21	HRC-S	LETG	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500799

Title: Constraining GRB phycis through their afterglow light curves

PI Name: Evert Rol

Our current understanding of gamma-ray burst afterglow light curves has become increasingly confused, and the validity of the standard synchrotron fireball model for GRBs is nowadays increasingly questioned. In particular, achromatic breaks due to the the lateral expansion of the GRB jet are not substantiated by Swift X-ray observations. It is only through this that the true energies of GRBs are constrained, and questions such as the true rate of GRBs and the determination of cosmological parameters are based upon it. We propose to use CXO to construct the late time X-ray light curves for several Swift bursts. These observations will search for evidence of achromatic jet breaks, providing the necessary insight into the GRB evolution, and the energy and activity of the central engine.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
		GRB	ACIS-S	NONE	21

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500803

Title: Testing Shock Physics Through Flux Variability in Cas A

PI Name: Daniel Patnaude

Cassiopeia A has recently joined SN 1987A and RXJ 1713-3946 as one of only a handful of SNRs to exhibit temporal variations in their thermal and nonthermal emission. We propose for three 50 ks observations of Cas A spaced in 6 month intervals. These new observations are designed to test for emission variability on short timescales. Consequently, they will discriminate between several models for rapid variability in the emission from nonthermal filaments. Furthermore, with these new observations, we will identify freshly reverse-shock heated ejecta, thus allowing us to measure the dynamics and chemical composition of the most pristine supernova debris.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
23:23:26.70	+58:49:03.00	Cassiopeia A	ACIS-S	NONE	100

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500804

Title: Confirming and exploring the supernova remnant candidate G308.3-1.4

PI Name: Chung Yue Hui

ROSAT all-sky survey (RASS) data have provided another window to search for supernova remnants (SNRs). Utilizing this database, the first catalogue of extended X-ray sources as promising SNR candidates was published ten years ago. However, these targets have not yet been fully explored by the state-of-art X-ray observatories. We have reexamined this catalogue and chosen the brightest SNR candidate, G308.3-1.4, for a detailed spectro-imaging X-ray study with Chandra. We propose a short ACIS-I imaging observation to have a full coverage of G308.3-1.4 in order to investigate its spectrum and morphology in details as well as to search for the associated compact stellar remnants produced in the supernova explosion.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
13:40:54.50	-63:43:06.00	G308.3-1.4	ACIS-I	NONE	15

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500846

Title: Tracking the X-ray Evolution of the Enigmatic SN1996cr

PI Name: Franz Bauer

SN1996cr is one of the five closest SNe to explode in the past 3 decades, yet lay hidden for many years. Its unique temporal evolution suggests that it exploded into a compact wind-blown bubble or shell, similar to SN1987A but >1000x more luminous. Recent observations now show a 20% decline, implying that the shock may have finally overtaken the shell. The nature of this new decline has important implications for the CSM created during the last 100-10,000 yrs by the progenitor, an epoch traditionally difficult to probe in massive stars. Along with ongoing ATCA and VLBA radio monitoring, an accurate well-sampled X-ray light curve is vital for setting strong constraints on the structure of the nebula established by progenitor winds and, by extension, the evolution of the progenitor itself.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
14:13:10.00	-65:20:44.50	SN1996cr	ACIS-S	NONE	20

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500865

Title: The long tail of PSR J1740+1000

PI Name: Oleg Kargalstev

An XMM-Newton observation of a 100-kyr-old PSR J1740+1000 revealed a 2-pc long linear feature, most likely a tail behind the supersonically moving pulsar. X-ray observations of such structures are particularly interesting because the entire pulsar wind flow is channeled into a narrow tail,thus making it possible to detect the shocked wind at large distances from the pulsar. Therefore, spatially-resolved spectroscopy and high-resolution imaging of pulsar tails are extremely useful for studying the evolution of cooling pulsar winds and the properties of relativistic MHD flows. Along the entire 5' length, the tail of PSR J1740+1000 is extremely well collimated, with the width of <40'', making Chandra ACIS the only instrument capable of studying the structure of the tail.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:40:24.30	+09:59:22.40	PSR J1740+1000	ACIS-I	NONE	70

Subject Category: SN, SNR AND ISOLATED NS

Proposal Number: 11500877

Title: Constraining the Distance & Temperature of LAT PSR J1742-20, The Newly Discovered Nearby Middle-Aged Neutron Star

PI Name: Gregory Sivakoff

The recent launch of Fermi has resulted in the discovery, in a blind search, of at least 14 previously unknown pulsars. One of these, LAT PSR J1742-20, has recently been identified as a radio pulsar. It has an estimated distance of 400 pc and characteristic age of 0.4 Myr making LAT PSR J1742-20 one of only three identified middle aged pulsars within 1 kpc. We have identified a SWIFT source as the likely X-ray counterpart. X-ray emission of middle aged pulsars is often dominated by its thermal component, which can be studied to constrain properties of the neutron star. We propose a 50ks ACIS-S observation of J1742-20 to provide the first accurate measurements of its thermal temperature and distance, and search for a potential pulsar wind nebula.

R.A.	Dec.	Target Name	Det.	Grating	Exp.Time
17:41:57.80	-20:54:11.90	LAT PSR J1742-20	ACIS-S	NONE	50

The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA. Email: cxchelp@head.cfa.harvard.edu Smithsonian Institution, Copyright © 1998-2025. All rights reserved.