View X-Atlas Observation

Observation ID	Observation Date	Target	Star Name	Object Class	Spectral Type	B-V Magnitude	RA (deg)	DEC (deg)	Exposure (s)
640	2000-03-28 13:31:41	Zeta Pup	HD 66811	Variable of BY Dra type	O4I(n)f	-0.2760	120.896040	-40.003150	67638.14

Chandra Configuration for the Observation

Zeroth-Order Image

Zeroth-Order Events	Zeroth-Order Count Rate (cts/s)	Pileup
13200	0.1952	severe

The zeroth-order image for Zeta Pup

Hardness Ratios and Quantiles

Hardness ratios and quantiles are calculated from the predicted ACIS-S or ACIS-I aimpoint spectra, as indicated.

Hardness Ratios
Aimpoint	HR₁ = (H-M)/(H+M)	HR₂ = (M-S)/(M+S)	HR₃ = (H-S)/(H+S)
ACIS-S	-0.631	-0.068	-0.671
ACIS-I	-0.602	0.155	-0.493

S, M, and H represent the predicted total counts in the following passbands:

S: 0.3-0.9 keV

M: 0.9-1.5 keV

H: 1.5-8.0 keV

Quantiles
Aimpoint	Quantiles	25 %	25 % Error	50 %	50 % Error	75 %	75 % Error
ACIS-S	keV	0.767	0.003	0.913	7.088	1.161	0.000
ACIS-S	Q-norm	0.061	0.000	0.080	0.920	0.112	0.000
ACIS-I	keV	0.840	0.005	1.000	0.001	1.278	0.002
ACIS-I	Q-norm	0.070	0.001	0.091	0.000	0.127	0.000

Normalized quantiles (Q-norm) are defined as:

Q_x = (E_x - E_lo)/(E_hi - E_lo)

Where E_lo = 0.3 keV and E_hi = 8.0 keV.

Hardness Ratio plots and Quantile-based Color-Color Diagrams

X-Atlas Hardness Ratios and Quantiles Listing

Spectral Metrics

A series of line-line, line-continuum, and continuum-continuum ratios calculated from the high-resolution 1^st order MEG or LEG spectrum.

Line-Line Ratios
Ne X / O VIII	Ne2O Error	O VII(i) / O VII(f)	Oif Error	O VII(r) / O VIII	O78 Error	O VIII / Fe XVII	O8Fe Error	Mg XII / Fe XVII	Mg2Fe Error	Si XIV / Fe XVII	Si2Fe Error	S XV / Fe XVII	S2Fe Error
7.0340	2.0741	0.0000	0.0000	0.3732	0.1706	0.0382	0.0101	0.0827	0.0217	0.0415	0.0158	0.1773	0.0525

short line / cont

Line-Continuum & Continuum-Continuum Ratios
sl2c Error	long line / cont	ll2c Error	line / cont	l2c Error	cont long / cont short	cl2cs Error	cont long / cont med	cl2cm Error	cont med / cont short	cm2cs Error
0.0083	0.0004	0.0044	0.0003	0.0137	0.0005	0.1007	0.0002	0.1015	0.0002	125.2031	0.5304

X-Atlas Spectral Metrics Listing

Spectral Fits

Image File Missing: 2T xsmekal zeroth-order fit
Mewe-Kaastra-Liedahl 2-temperature fit of the low-resolution zeroth-order spectrum of Zeta Pup.
Warning: The zeroth-order spectrum may be subject to distortions from pileup.

Image File Missing: 2T xsmekal ACIS-S fit
Mewe-Kaastra-Liedahl 2-temperature fit of the predicted low-resolution ACIS-S Aimpoint spectrum of Zeta Pup. The predicted spectrum was scaled to 1500 counts.

Image File Missing: 2T xsmekal ACIS-I fit
Mewe-Kaastra-Liedahl 2-temperature fit of the predicted low-resolution ACIS-I Aimpoint spectrum of Zeta Pup. The predicted spectrum was scaled to 1500 counts.

Aimpoint	Model	nH (10²²/cm³)	nH error	kT (keV)	kT error	kT2 (keV)	kT2 error	Abundance (solar)	Abundance error	Flux (ergs/cm²/s)	Flux Emission Ratio (kT2/kT1)	Reduced Chi²	DoF
zeroth-order	xswabs*(xsmekal1+xsmekal2)	0.070		0.846		0.010		0.03		0	0	3.58	202
ACIS-S	xswabs*(xsmekal1+xsmekal2)	0.030		1.212		0.603		0.14		9.20705e-14	2.46248	1.33	57
ACIS-I	xswabs*(xsmekal1+xsmekal2)	0.030		1.946		0.670		0.12		1.51325e-13	8.21779	1.70	59

X-Atlas Spectral Fits Listing

HETG Light Curve

GLvary
Odds	-1.153
Prob.	0.066
Var. Index	0

HETG light curve for Zeta Pup, constructed from all ±1^st, ±2^nd, and ±3^rd order HETG events.

HETG HEG Spectrum

Image File Missing: High-Resolution 1st Order HEG spectrum of obsid 640

High-Resolution 1st Order HEG Spectrum for Zeta Pup

HETG MEG Spectrum

Image File Missing: High-Resolution 1st Order MEG Spectrum of obsid 640

High-Resolution 1st Order MEG Spectrum for Zeta Pup

X-Atlas Data Products

Spectral Data
PHA II	HEG ±1^st Order PHA	HEG ±1^st Order gARF	MEG ±1^st Order PHA	MEG ±1^st Order gARF	[Counts/s/Å] FITS	[Counts/s/Å] text	[ph/s/Å/cm²] FITS	[ph/s/Å/cm²] text

Standard Data Products (Cycle 06)
Aimpoint ARF		Aimpoint RMF
ACIS-S	ACIS-I	ACIS-S	ACIS-I

Retrieve observation data from the Chandra Data Archive: WebChaSeR

Target Preview