J/ApJ/740/L34 Chandra monitoring of QSO J2240+0321 (Chen+, 2011)
Discovery of energy-dependent X-ray microlensing in Q2237+0305.
Chen B., Dai X., Kochanek C.S., Chartas G., Blackburne J.A., Kozlowski S.
<Astrophys. J., 740, L34 (2011)>
=2011ApJ...740L..34C 2011ApJ...740L..34C
ADC_Keywords: Gravitational lensing ; QSOs ; X-ray sources
Keywords: accretion, accretion disks - black hole physics -
gravitational lensing: micro - gravitational lensing: strong -
quasars: individual (Q2237+0305)
Abstract:
We present our long-term Chandra X-ray monitoring data for the
gravitationally lensed quasar Q2237+0305 with 20 epochs spanning 10
years. We easily detect microlensing variability between the images in
the full (0.2-8keV), soft (0.2-2keV), and hard (2-8keV) bands at
very high confidence. We also detect, for the first time, chromatic
microlensing differences between the soft and hard X-ray bands. The
hard X-ray band is more strongly microlensed than the soft band,
suggesting that the corona above the accretion disk thought to
generate the X-rays has a non-uniform electron distribution, in which
the hotter and more energetic electrons occupy more compact regions
surrounding the black holes. Both the hard and soft X-ray bands are
more strongly microlensed than the optical (rest-frame UV) emission,
indicating that the X-ray emission is more compact than the optical,
confirming the microlensing results from other lenses.
Description:
In various combinations, we have now observed Q2237+0305 with ACIS on
board the Chandra X-Ray Observatory for 20 epochs between 2000
September and 2010 November (Table 1).
Objects:
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RA (2000) DE Designation(s)
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22 40 30.3 +03 21 30 Q2237+0305 = QSO J2240+0321
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 49 80 Chandra count rates of Q2237+0305 corrected for
absorption
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2012)
V/134 : Atlas of Radio/X-ray associations (ARXA) (Flesch, 2010)
IX/41 : XMM-Newton Serendipitous Source Catalogue 2XMMi-DR3 (XMM-SSC, 2010)
J/A+A/493/339 : XMM-Newton serendipitous Survey. V. (Watson+, 2009)
J/ApJS/169/401 : ChaMP X-ray point source catalog (Kim+, 2007)
J/AZh/84/885 : VRI observations of radio source S5 0716+71 (Koptelova+, 2007)
J/A+A/420/447 : VRI photometry of lensed QSO B2237+0305 (Vakulik+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ObsID [431/13195] Chandra observation number
7- 11 I5 d JD [51794/55528] Julian Date (JD-2400000)
13- 17 I5 s Exp [7264/30287] Exposure time
19 A1 --- Image [A-D] Image identification (1)
21- 25 F5.1 ct/ks CRfull [2/211.9] Full 0.2-8keV band count rate
27- 30 F4.1 ct/ks e_CRfull [0.5/14.5] Uncertainty in CRfull
32- 36 F5.1 ct/ks CRsoft [1.5/197.2] Soft 0.2-2keV band count rate
38- 40 F3.1 ct/ks e_CRsoft [0.4/9.7] Uncertainty in CRsoft
42- 45 F4.1 ct/ks CRhard [0.3/22.7] Hard 2-8keV band count rate
47- 49 F3.1 ct/ks e_CRhard [0.2/2.1] Uncertainty in CRhard
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Note (1): We obtained a stacked image of Q2237+0305 (Figure 1) based on the
image positions obtained from the PSF fitting results. See section 2.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Feb-2013