Search Publications
PSR J1306-40: An X-Ray Luminous Redback with an Evolved Companion
Strader, Jay; Chomiuk, Laura; Shishkovsky, Laura +1 more
PSR J1306-40 is a millisecond pulsar (MSP) binary with a non-degenerate companion in an unusually long ∼1.097 day orbit. We present new optical photometry and spectroscopy of this system, and model these data to constrain fundamental properties of the binary such as the component masses and distance. The optical data imply a minimum neutron star m…
Evidence of Nonluminous Matter in the Center of M62
Colpi, Monica; Possenti, Andrea; Abbate, Federico +1 more
Theoretical models suggest that intermediate-mass black holes (IMBHs) may form and reside in the centers of globular clusters. IMBHs are still elusive to observations, but the accelerations of pulsars may bring along a unique fingerprint of their presence. In this work, we focus on the pulsars in the globular cluster M62. Using the new distance of…
An ALMA Study of the FU Ori-type Object V900 Mon: Implications for the Progenitor
Dong, Ruobing; Takami, Michihiro; Ábrahám, Péter +13 more
We present ALMA observations of 12CO, 13CO, and C18O J = 2-1 lines and the 230 GHz continuum for the FU Ori-type object (FUor) V900 Mon (d ∼ 1.5 kpc), for which the accretion burst was triggered between 1953 and 2009. We identified CO emission associated with a molecular bipolar outflow extending up to an ∼104…
Cloud Atlas: Variability in and out of the Water Band in the Planetary-mass HD 203030B Points to Cloud Sedimentation in Low-gravity L Dwarfs
Schneider, Glenn; Metchev, Stanimir; Apai, Dániel +11 more
We use the Wide Field Camera 3 on the Hubble Space Telescope to spectrophotometrically monitor the young L7.5 companion HD 203030B. Our time series reveal photometric variability at 1.27 and 1.39 µm on timescales compatible with rotation. We find a rotation period of {7.5}-0.5+0.6 hr: comparable to those observed in oth…
Application of Clumpy Torus Model to Broadband X-Ray Spectra of Two Seyfert 1 Galaxies: IC 4329A and NGC 7469
Tanimoto, Atsushi; Ueda, Yoshihiro; Kawaguchi, Toshihiro +2 more
We apply a new X-ray clumpy torus model, XCLUMPY, in which the clump distribution is assumed to be the same as that in the infrared clumpy torus model (CLUMPY) by Nenkova et al., to the broadband X-ray spectra of type-1 active galactic nuclei (AGNs) for the first time. We analyze the archival data of IC 4329A and NGC 7469 observed with NuSTAR/Suza…
HALO7D I. The Line-of-sight Velocities of Distant Main-sequence Stars in the Milky Way Halo
Barro, Guillermo; Guhathakurta, Puragra; Kirby, Evan N. +5 more
The Halo Assembly in Lambda-CDM: Observations in 7 Dimensions (HALO7D) data set consists of Keck II/DEIMOS spectroscopy and Hubble Space Telescope-measured proper motions of Milky Way halo main-sequence turnoff stars in the CANDELS fields. In this paper, we present the spectroscopic component of this data set and discuss target selection, observin…
A Closer Look at Some Gas-phase Depletions in the ISM: Trends for O, Ge, and Kr versus {F}_{* }, f(H2), and Starlight Intensity
Jenkins, Edward B.
In a survey of archived ultraviolet spectra of 100 stars recorded by the echelle spectrograph of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, we measure the strengths of the weak absorption features of O I, Ge II, and Kr I in the interstellar medium. Our objective is to undertake an investigation that goes beyond earlier…
Interaction of SN Ib 2004dk with a Previously Expelled Envelope
Wheeler, J. Craig; Silverman, Jeffrey M.; Pooley, David +7 more
The interaction between the expanding supernova (SN) ejecta with the circumstellar material (CSM) that was expelled from the progenitor prior to explosion is a long-sought phenomenon, yet observational evidence is scarce. Here we confirm a new example: SN 2004dk, originally a hydrogen-poor, helium-rich Type Ib SN that reappeared as a strong {{H}}α…
Detection and Classification of Supernovae Beyond z ∼ 2 Redshift with the James Webb Space Telescope
Vinkó, József; Regős, Enikő
Future time-domain surveys for transient events in the near- and midinfrared bands will significantly extend our understanding about the physics of the early universe. In this paper we study the implications of a deep (∼27 mag), long-term (∼3 yr), observationally inexpensive survey with the James Webb Space Telescope (JWST) within its Continuous V…
Spectroscopic and Stereoscopic Observations of the Solar Jets
Feng, Li; Lu, Lei; Gan, Weiqun +3 more
We present a comprehensive study of a series of recurrent jets that occurred at the periphery of the NOAA active region 12114 on 2014 July 7. These jets were found to share the same source region and exhibited rotational motions as they propagated outward. The multiwavelength imaging observations made by the AIA and IRIS telescopes reveal that som…