Kayhan Gültekin

I am an assistant professor at the University of Michigan, Department of Astronomy. I study astrophysical black holes and their relationship with their hosts, be they galaxy nuclei, dark matter halos, stellar clusters, or whatever.

News

2015 Oct 26 — I am advertising for a postdoctoral position (AAS Job Register advertisement) starting in the Fall 2016.

2015 Jun 24 — Our orbit modeling of new data for Mrk 1216 and NGC 1277, Yıldırım et al. has been accepted by MNRAS and posted to astro-ph. New (high) upper limit to the black hole mass in Mrk 1216 of $$\log(M/\msun) < 10.0\ \,$$ at 99.7% confidence and an H-band mass-to-light ratio of $$\Upsilon_H = 1.8_{-0.8}^{+0.5}\,\msun\,L_{\scriptscriptstyle \odot,H}^{-1}\ \,$$.

2015 Jun 18 — Our measurement of the black hole in NGC 1271, Walsh et al. has been accepted by ApJ and posted to astro-ph. The mass of the black hole is $$M = 3.0_{-1.1}^{+1.0} \ \times 10^9\, M_{\scriptscriptstyle \odot}\ \,$$.

2015 Mar 26 — Don’t forget to register for the Third Annual Compact Objects in Michigan meeting.

2015 Mar 10 — We just submitted “Swift/UVOT grism moitoring of NGC 5548 in 2013: an attempt at MgII reverberation mapping” by Cackett et al. to ApJ and posted to astro-ph. As you might guess from the title, we were not able to positively measure a lag, but I think we are showing that very interesting things can be done with Swift.

2015 Feb 5 — At long last, our HET Massive Galaxy Survey (HETMGS), ven den Bosch et al. has been accepted by ApJS and posted to astro-ph. A catalog of stellar velocity dispersions in 1022 galaxies!

2014 Dec 15 — We recently published ATEL 6825 on “X-ray Absorption Lines in the Candidate Tidal Disruption Event ASASSN-14li.” This thing is weird/fascinating.

2014 Dec 15 — We recently published ATEL 6800 on “Chandra LETG Spectroscopy of Tidal Disruption Candidate ASASSN-14li.”

2014 Dec 11 — I have been very bad about reporting news for the past several months, even though there has been a lot! I will catch up with the backlog, but in the meantime: Our recent paper Ludlam et al. (2014), “X-ray Spectral and Variability Properties of Low-Mass AGN,” has been accepted by MNRAS and posted to astro-ph. Renee Ludlam, the first author, is a talented undergrad and will be applying to grad school this year; so keep your eye open for her!

2014 May 20 — Our recent paper Bellovary et al. (2014), “Effects of Inclination on Measuring Velocity Dispersion and Implications for Black Holes,” has been submitted to MNRAS and posted to astro-ph.

2014 May 29 — Our recent paper Gültekin et al. (2014), “Low-Mass AGN and Their Relation to the Fundamental Plane of Black Hole Accretion,” has been accepted by ApJL and posted to astro-ph.

2014 May 20 — Our recent paper Bellovary et al. (2014), “Effects of Inclination on Measuring Velocity Dispersion and Implications for Black Holes,” has been submitted to MNRAS and posted to astro-ph.

2014 March 6 — Our recent paper Degenaar et al. (2014), “Multi-Wavelength Coverage of State Transitions in the New Black Hole X-ray Binary Swift J1910.2−0546,” has been accepted by ApJ and posted to astro-ph.

2013 December 18 — Our recent paper Gultekin et al. (2013), “The Black Hole Mass and the Stellar Ring in NGC 3706,” has been accepted by ApJ and posted to astro-ph. We measure the black hole mass and come to the surprising conclusion that the stellar ring in NGC 3706 has stars that orbit in both directions.