Search Publications
Robotic Reverberation Mapping of the Southern Seyfert NGC 3783
Onken, Christopher A.; Bentz, Misty C.; Valluri, Monica +1 more
We present spectroscopic and photometric monitoring of NGC 3783 conducted throughout the first half of 2020. Time delays between the continuum variations and the response of the broad optical emission lines were clearly detected, and we report reverberation measurements for Hβ, He II λ4686, Hγ, and Hδ. From the time delay in the broad Hβ emission …
Thermal Emission and Radioactive Lines, but No Pulsar, in the Broadband X-Ray Spectrum of Supernova 1987A
Fransson, Claes; Alp, Dennis; Larsson, Josefin
Supernova 1987A offers a unique opportunity to study an evolving supernova in unprecedented detail over several decades. The X-ray emission is dominated by interactions between the ejecta and the circumstellar medium, primarily the equatorial ring (ER). We analyze 3.3 Ms of NuSTAR data obtained between 2012 and 2020, and two decades of XMM-Newton …
Compact Starburst Galaxies with Fast Outflows: Central Escape Velocities and Stellar Mass Surface Densities from Multiband Hubble Space Telescope Imaging
Moustakas, John; Coil, Alison L.; Rudnick, Gregory H. +21 more
We present multiband Hubble Space Telescope imaging that spans rest-frame near-ultraviolet through near-infrared wavelengths ( ${\lambda }_{\mathrm{rest}}=0.3$ -1.1 µm) for 12 compact starburst galaxies at z = 0.4-0.8. These massive galaxies ( ${{ \mathcal M }}_{* }\sim {10}^{11}\,{{ \mathcal M }}_{\odot }$ ) are driving very fast outflows (…
Pursuing the Origin of the Gamma Rays in RX J1713.7-3946 Quantifying the Hadronic and Leptonic Components
Inoue, Tsuyoshi; Tachihara, Kengo; Fukui, Yasuo +5 more
We analyzed the TeV gamma-ray image of a supernova remnant RX J1713.7-3946 (RX J1713) through a comparison with the interstellar medium (ISM) and nonthermal X-rays. The gamma-ray data sets at two energy bands of >2 TeV and >250-300 GeV were obtained with H.E.S.S. and utilized in the analysis. We employed a new methodology, which assumes that…
Deciphering the Kinematic Structure of the Small Magellanic Cloud through Its Red Giant Population
van der Marel, Roeland P.; Kallivayalil, Nitya; Zivick, Paul
We present a new kinematic model for the Small Magellanic Cloud (SMC), using data from the Gaia Data Release 2 catalog. We identify a sample of astrometrically well-behaved red giant (RG) stars belonging to the SMC and cross-match with publicly available radial velocity (RV) catalogs. We create a 3D spatial model for the RGs, using RR Lyrae for di…
An Exquisitely Deep View of Quenching Galaxies through the Gravitational Lens: Stellar Population, Morphology, and Ionized Gas
Richard, Johan; Zibetti, Stefano; Brammer, Gabriel B. +6 more
This work presents an in-depth analysis of four gravitationally lensed red galaxies at z = 1.6-3.2. The sources are magnified by factors of 2.7-30 by foreground clusters, enabling spectral and morphological measurements that are otherwise challenging. Our sample extends below the characteristic mass of the stellar mass function and is thus more re…
An Unbiased CO Survey toward the Northern Region of the Small Magellanic Cloud with the Atacama Compact Array. I. Overview: CO Cloud Distributions
Tokuda, Kazuki; Tachihara, Kengo; Kawamura, Akiko +15 more
We have analyzed the data from a large-scale CO survey toward the northern region of the Small Magellanic Cloud (SMC) obtained with the Atacama Compact Array (ACA) stand-alone mode of ALMA. The primary aim of this study is to comprehensively understand the behavior of CO as an H2 tracer in a low-metallicity environment (Z ~ 0.2 Z ⊙…
On the Occurrence of Type IV Solar Radio Bursts in Solar Cycle 24 and Their Association with Coronal Mass Ejections
Kilpua, E. K. J.; Kumari, Anshu; Morosan, D. E.
Solar activities, in particular coronal mass ejections (CMEs), are often accompanied by bursts of radiation at meter wavelengths. Some of these bursts have a long duration and extend over a wide frequency band, namely, type IV radio bursts. However, the association of type IV bursts with CMEs is still not well understood. In this article, we perfo…
Mid-infrared Period-Luminosity Relations for Miras in the Large Magellanic Cloud
Soszyński, Igor; Kozłowski, Szymon; Iwanek, Patryk
We present the mid-infrared (mid-IR) period-luminosity relations (PLRs) using over 1000 Mira variables in the Large Magellanic Cloud, for the four Wide-field Infrared Survey Explorer and the four Spitzer bands. These PLRs cover a mid-IR wavelength range from 3.4-22 µm and are presented separately for the oxygen-rich (O-rich) and carbon-rich …
Observational Signatures of Cosmic-Ray Interactions in Molecular Clouds
Wu, Kinwah; Lai, Shih-Ping; On, Alvina Y. L. +1 more
We investigate ionization and heating of gas in the dense, shielded clumps/cores of molecular clouds bathed by an influx of energetic, charged cosmic rays (CRs). These molecular clouds have complex structures, with substantial variation in their physical properties over a wide range of length scales. The propagation and distribution of CRs is thus…