HE 1104−1805
Gravitationally lensed quasar in the constellation Crater
From Wikipedia, the free encyclopedia
HE 1104−1805 known as CTS 463[2] or Double Hamburger in literature,[3] is a gravitationally-lensed quasar[4] located in the constellation of Crater. It has a redshift of (z) 2.32[1] and it was first discovered by astronomers L. Wisotzki, T. Koehler, R. Kayser and D. Reimers in October 1993.[5] This quasar is classified as radio-quiet.[6]
| HE 1104−1805 | |
|---|---|
Image of the gravitationally lensed quasar HE 1104−1805 | |
| Observation data (J2000.0 epoch) | |
| Constellation | Crater |
| Right ascension | 11h 06m 33.40s[1] |
| Declination | −18° 21′ 23.00″[1] |
| Redshift | 2.322200[1] |
| Heliocentric radial velocity | 696,178 km/s[1] |
| Distance | 10.490 Gly |
| Apparent magnitude (V) | 15.9[2] |
| Apparent magnitude (B) | 15.8[2] |
| Characteristics | |
| Type | RQQ[1] |
| Other designations | |
| Name Double Hamburger, CTS 463, QSO B1104−181, INTREF 439, SDSS J110633.38−182123.7, TIC 410396549, 6dFGS gJ110633.5−182124[2] | |
Description
HE 1104−1805 is classified as a double quasar with an angular separation of 3.0 arcseconds and estimated B magnitudes of 16.70 and 18.74.[7][5] When imaged, the quasar is found separated into two components, with the A component displaying emission lines of lower width, and a bluer continuum.[5] It is found lensed by a foreground early-type galaxy described as large with a mass of 7 × 1011 M☉.[8][9] The redshift of the lens galaxy is (z) 0.729 ± 0.001 based on observations with the Very Large Telescope by C. Lidman[10] while dismissing other redshift estimates of the galaxy at (z) 0.77 by C.Y. Peng based on the assumption of a fundamental plane measurement made by C.S. Kochanek[9][11] and at (z) 1.66 by F. Courbin.[8]
Combined observations with the Wise Observatory and by Schechter found the two images of HE 1104−1805 display time-delays. Based on results, the time delays are significantly shorter with a period of -161 ± 7 days while others estimated the time-delays between the ranges of -129 and -263 h−1 days,[12] 0.73 years via a quantitative analysis,[13] and between -0.9 and -0.7 years.[14] Another study estimated an interband centroid time-delay of -4.3+3.1-3.4 days.[15]
Evidence also showed the light curves of the two images displaying a long-term variability trend, indicating it was caused by microlensing from the stars of the lens galaxy.[12] Substantial variations were also noted in these images, although the B image has less fluctuations compared to the A image mainly because of the high dark matter concentration and low stellar surface density.[16] Monitoring campaign observations made with Chandra X-ray Observatory in 2009, also detected the flux variability of the A image of HE 1104–1805 has a high amplitude in X-rays. As the variability is uncorrelated, this indicates microlensing.[17]
The host galaxy of HE 1104−1805 is described as shaped into an Einstein Ring. It has a dusty appearance or little star formation based on scaling and addition of its arc imaging to both I and V images.[9] Observations also pointed out the carbon oxide emission are found associated with the AGN's two point-like imaging with offset emission peaks. This suggests the AGN is not located in the molecular gas reservoir.[6]
The central supermassive black hole of HE 1104−1805 is estimated to be 2.4 × 109 M☉.[6] Other studies estimated the black hole mass as 9.37 ± 0.33, 8.77 ± 30 and 9.05 ± 0.23 based on estimation of its emission line widths.[18] Several rich metallic systems of absorption lines have also been identified in the quasar's spectra with these lines being located at (z) 1.662, (z) 0.728 and (z) 1.320.[19][20][10]
Gallery
