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Observation ID Observation Date Target Star Name Object Class Spectral Type B-V Magnitude RA (deg) DEC (deg) Exposure (s)
4899 2004-05-28 04:47:04 NGC 4945 IRAS 13025-4911 Seyfert 2 Galaxy Scr... D ~ 1.3600 196.364510 -49.467950 77369.90

Chandra Configuration for the Observation

Zeroth-Order Image

Image File Missing: Snapshot of the Zeroth-Order Image
Zeroth-Order Events Zeroth-Order Count Rate (cts/s) Pileup
1570 0.0203 mild
The zeroth-order image for NGC 4945

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 0.861 -0.653 0.475
ACIS-I 0.904 -0.441 0.770
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 0.913 0.026 3.774 0.075 5.687 0.107
Q-norm 0.080 0.003 0.451 0.010 0.700 0.014
ACIS-I keV 2.911 0.136 4.460 0.060 6.271 0.025
Q-norm 0.339 0.018 0.540 0.008 0.775 0.003
Normalized quantiles (Q-norm) are defined as:
Qx = (Ex - Elo)/(Ehi - Elo)
Where Elo = 0.3 keV and Ehi = 8.0 keV.
Hardness Ratio plots and Quantile-based Color-Color DiagramsX-Atlas Hardness Ratios and Quantiles Listing

Spectral Metrics

A series of line-line, line-continuum, and continuum-continuum ratios calculated from the high-resolution 1st 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
0.0000 0.0000 0.0000 0.0000 0.9698 6.2981 7.1236 82.9362 6.9924 81.3434 12.6808 142.5091 20.4897 224.3732

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
0.8275 0.3439 0.2874 3.3284 1.1150 3.3463 0.5284 0.0366 13.0441 20.9284 0.0422 0.0677
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 NGC 4945.
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 NGC 4945. 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 NGC 4945. 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) 10.000 50.000 0.224 1.50 9.03137e-13 947.168 4.51 72
ACIS-S xswabs*(xsmekal1+xsmekal2) 0.000 30.000 1.000 1.49 4.00669e-14 0 14.14 85
ACIS-I xswabs*(xsmekal1+xsmekal2) 6.903 30.000 1.000 1.50 3.5817e-13 0 6.55 84
X-Atlas Spectral Fits Listing

HETG Light Curve

Image File Missing: HETG Light Curve
GLvary
Odds36.277
Prob.1.000
Var. Index10
HETG light curve for NGC 4945, constructed from all ±1st, ±2nd, and ±3rd order HETG events.

HETG HEG Spectrum

Image File Missing: High-Resolution 1st Order HEG spectrum of obsid 4899
High-Resolution 1st Order HEG Spectrum for NGC 4945

HETG MEG Spectrum

Image File Missing: High-Resolution 1st Order MEG Spectrum of obsid 4899
High-Resolution 1st Order MEG Spectrum for NGC 4945

X-Atlas Data Products

Spectral Data
PHA II HEG ±1st Order PHA HEG ±1st Order gARF MEG ±1st Order PHA MEG ±1st 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 ARFAimpoint RMF
ACIS-SACIS-IACIS-SACIS-I
Retrieve observation data from the Chandra Data Archive: WebChaSeR
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