J/ApJ/660/146 HE 1104-1805 differential light curves (Poindexter+, 2007)
Mid-IR observations and a revised time delay for the gravitational lens system
quasar HE 1104-1805.
Poindexter S., Morgan N., Kochanek C.S., Falco E.E.
<Astrophys. J., 660, 146-151 (2007)>
=2007ApJ...660..146P 2007ApJ...660..146P
ADC_Keywords: QSOs ; Photometry
Keywords: gravitational lensing - quasars: general -
quasars: individual (HE 1104-1805)
Abstract:
The mid-IR flux ratios FA/FB=2.84±0.06 of the two images of the
gravitationally lensed quasar HE 1104-1805 show no wavelength
dependence to within 3% across 3.6-8.0um, show no time dependence
over 6 months, and agree with the broad emission-line flux ratios.
This indicates that the mid-IR emission likely comes from scales large
enough to be little affected by microlensing and that there is little
differential extinction between the images. We measure a revised time
delay between these two images of 152.2+2.8-3.0 (1sigma) days from
R- and V-band data covering the years 1997-2006. This time delay
indicates that the lens has an approximately flat rotation curve over
scales of 1-2Re. We also observed uncorrelated variations of
∼0.05mag/yr, which we attribute to microlensing of the optical
emission from the accretion disk. The optical colors have also changed
significantly in the sense that image A is now redder than image B,
rather than bluer, as it was in 1993.
Description:
HE 1104-1805 was originally observed with HST by Lehar et al.
(2000ApJ...536..584L 2000ApJ...536..584L), but we obtained deeper NICMOS NIC2 F160W (H
band) observations as part of GO-9375 on 2003 December 17 (HJD
2452990.9), with the aim of improving the lens galaxy astrometry and
profile and studying the quasar host galaxy.
We observed HE 1104-1805 with Spitzer and the Infrared Array Camera
(IRAC) on 2005 June 15 and 2006 January 2 as part of Spitzer program
20451.
Objects:
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RA (2000) DE Designation(s)
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11 06 33.5 -18 21 24 HE 1104-1805 = QSO B1104-1805
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 65 208 Light Curves for HE 1104-1805
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Table 2: Relative astrometry and photometry for field reference stars
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ID oRA oDE DRmag DJmag
arcsec arcsec mag mag
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1 -3.4 -15.1 0 0
2 31.8 -5.3 0.731±0.002 ---
3 -45.7 23.8 0.604±0.002 0.653±0.009
4 33.6 119.3 -0.003±0.003 ---
5 -143.9 -64.4 -1.896±0.028 ---
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Note: The positions are measured with respect to HE 1104-1805 image A. The
magnitude differences are for the SMARTS R- and J-band data. For the
SOAR data, only star 1 (set to unity) was available as a local
reference star.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 F11.3 d HJD Heliocentric Julian Date
13- 16 F4.2 --- Rchi2 Reduced χ2
18- 23 F6.3 mag CompA Relative image A magnitude (1)
25- 29 F5.3 mag e_CompA Uncertainty in CompA (1)
31- 36 F6.3 mag CompB Relative image B magnitude (1)
38- 42 F5.3 mag e_CompB Uncertainty in CompB (1)
44- 49 F6.3 mag RStar ?=0. Average magnitude difference of reference
stars (2)
51- 55 F5.3 mag e_RStar ? Uncertainty in RStar
57- 62 A6 --- Tel [SMARTS SOAR] Telescope used
64- 65 A2 --- Filt [BIJR HJKs] Filter used
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Note (1): Relative to the local reference stars.
Note (2): Relative to the campaign mean. Values are 0 for the three
SOAR data points because we have only one epoch of data.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 04-Mar-2009