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Observation ID Observation Date Target Star Name Object Class Spectral Type B-V Magnitude RA (deg) DEC (deg) Exposure (s)
2418 2001-01-17 10:49:56 H1821+643 8C 1821+643A Seyfert 1 Galaxy undef -0.0100 275.488410 64.343350 51749.21

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
9701 0.1875 severe
The zeroth-order image for H1821+643

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 -0.040 -0.064 -0.103
ACIS-I 0.017 0.280 0.296
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 0.737 0.004 1.102 0.001 1.672 0.006
Q-norm 0.057 0.001 0.104 0.000 0.178 0.001
ACIS-I keV 0.956 0.001 1.321 0.001 1.920 0.008
Q-norm 0.085 0.000 0.133 0.000 0.210 0.001
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
1.8440 1.3297 0.0000 0.0000 0.8571 1.6016 0.6019 1.5082 0.0000 0.0000 4.5105 11.0700 1.2673 3.1491

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
0.0075 0.0003 0.0039 0.0003 0.0114 0.0004 0.0317 0.0001 0.0323 0.0001 51.4884 0.1280
X-Atlas Spectral Metrics Listing

Spectral Fits

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
X-Atlas Spectral Fits Listing

LETG Light Curve

Image File Missing: LETG Light Curve
GLvary
Odds-2.181
Prob.0.007
Var. Index0
LETG light curve for H1821+643, constructed from all ±1st, ±2nd, and ±3rd order LETG events.

LETG LEG Spectrum

Image File Missing: High-Resolution 1st Order LEG spectrum of obsid 2418
High-Resolution 1st Order LEG Spectrum for H1821+643

X-Atlas Data Products

Spectral Data
PHA II LEG ±1st Order PHA LEG ±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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