Search Publications
A detailed study on the reflection component for the black hole candidate MAXI J1836-194
Gou, Lijun; García, Javier A.; Liu, Zhu +3 more
We present a detailed spectral analysis of the black hole candidate MAXI J1836-194. The source was caught in the intermediate state during its 2011 outburst by Suzaku and RXTE. We jointly fit the X-ray data from these two missions using the relxill model to study the reflection component, and a steep inner emissivity profile indicating a compact c…
Extending the view of ArH+ chemistry in diffuse clouds
Wyrowski, Friedrich; Menten, Karl M.; Jacob, Arshia M. +2 more
Context. One of the surprises of the Herschel mission was the detection of ArH+ towards the Crab Nebula in emission and in absorption towards strong Galactic background sources. Although these detections were limited to the first quadrant of the Galaxy, the existing data suggest that ArH+ ubiquitously and exclusively probes t…
Infrared Properties of Asymptotic Giant Branch Stars in Our Galaxy and the Magellanic Clouds
Suh, Kyung-Won
We investigate the infrared properties of asymptotic giant branch (AGB) stars in our Galaxy and the Magellanic Clouds using various infrared observational data and theoretical models. We use catalogs for the sample of 4996 AGB stars in our Galaxy and about 39,000 AGB stars in the Magellanic Clouds from the available literature. For each object in …
A Larger Extent for the Ophiuchus Stream
Caldwell, Nelson; Price-Whelan, Adrian M.; Bonaca, Ana +2 more
We present new kinematic data for the Ophiuchus stellar stream. Spectra have been taken of member candidates at the MMT telescope using Hectospec, Hectochelle, and Binospec, which provide more than 1800 new velocities. Combined with proper-motion measurements of stars in the field by the Gaia—DR2 catalog, we have derived stream membership probabil…
Host galaxy properties and environment of obscured and unobscured X-ray selected active galactic nuclei in the COSMOS survey
Bornancini, C.; García Lambas, D.
We analyse different photometric and spectroscopic properties of active galactic nuclei (AGNs) and quasars (QSOs) selected by their mid-IR power-law and X-ray emission from the COSMOS survey. We use a set of star-forming galaxies as a control sample to compare with the results. We have considered samples of obscured (HR > -0.2) and unobscured (…
Cosmological 3D H I Gas Map with HETDEX Lyα Emitters and eBOSS QSOs at z = 2: IGM-Galaxy/QSO Connection and a ∼40 Mpc Scale Giant H II Bubble Candidate
Ono, Yoshiaki; Ouchi, Masami; Finkelstein, Steven L. +20 more
We present cosmological (30-400 Mpc) distributions of neutral hydrogen (H I) in the intergalactic medium (IGM) traced by Lyα emitters (LAEs) and QSOs at z = 2.1-2.5, selected with the data of the ongoing Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) and the eBOSS survey. Motivated by a previous study of Mukae et al., we investigate spatia…
Distance, magnetic field, and kinematics of the filamentary cloud LDN 1157
Tej, Anandmayee; Soam, Archana; Kim, Shinyoung +7 more
Context. LDN 1157 is one of several clouds that are situated in the cloud complex LDN 1147/1158. The cloud presents a coma-shaped morphology with a well-collimated bipolar outflow emanating from a Class 0 protostar, LDN 1157-mm, that resides deep inside the cloud.
Aims: The main goals of this work are (a) mapping the intercloud magnetic field…
The globular cluster M10: reassessment of stellar membership, distance, and age using its variable and HB stars
Arellano Ferro, A.; Calderón, J. H.; Muneer, S. +4 more
Time-series VI CCD photometry of the globular cluster M10 (NGC 6254) is employed to perform a detailed identification, inspection of their light curves, their classification, and their cluster membership, of all the known variables reported up to 2018. The membership analysis is based on the $Gaia$ -DR2 positions and proper motions. The metallicit…
Soft X-Ray Observations of Quiescent Solar Active Regions Using the Novel Dual-zone Aperture X-Ray Solar Spectrometer
Woods, Thomas N.; Caspi, Amir; Mason, James Paul +3 more
The Dual-zone Aperture X-ray Solar Spectrometer (DAXSS) was flown on 2018 June 18 on the NASA 36.336 sounding rocket flight and obtained the highest resolution to date for solar soft X-ray (SXR) spectra over a broad energy range. This observation was during a time with quiescent (nonflaring) small active regions on the solar disk and when the 10.7…
Massive Star Formation in the Ultraviolet Observed with the Hubble Space Telescope
Leitherer, Claus
Spectroscopic observations of a massive star formation in the ultraviolet and their interpretation are reviewed. After a brief historical retrospective, two well-studied resolved star clusters and the surrounding H II regions are introduced: NGC 2070 in the Large Magellanic Cloud and NGC 604 in M33. These regions serve as a training set for studie…