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Observation ID Observation Date Target Star Name Object Class Spectral Type B-V Magnitude RA (deg) DEC (deg) Exposure (s)
6867 2006-01-17 08:48:20 3C 279 QSO B1253-05 Quasar undef 0.0000 194.046490 -5.789410 28127.67

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
5783 0.2056 severe
The zeroth-order image for 3C 279

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 0.113 0.111 0.221
ACIS-I 0.169 0.410 0.542
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 0.883 0.005 1.321 0.006 2.066 0.012
Q-norm 0.076 0.001 0.133 0.001 0.229 0.002
ACIS-I keV 1.073 0.004 1.497 0.007 2.519 0.021
Q-norm 0.100 0.001 0.155 0.001 0.288 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 3.4355 17.1577 0.0000 0.0000 0.0000 0.0000 0.9157 1.3904 1.2209 1.8388 0.7116 1.0817

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
0.0130 0.0007 0.0057 0.0013 0.0189 0.0015 0.0476 0.0002 0.0515 0.0002 12.1262 0.0335
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-1.906
Prob.0.012
Var. Index0
LETG light curve for 3C 279, constructed from all ±1st, ±2nd, and ±3rd order LETG events.

LETG LEG Spectrum

Image File Missing: High-Resolution 1st Order LEG spectrum of obsid 6867
High-Resolution 1st Order LEG Spectrum for 3C 279

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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