Search Publications
On the Possibility of Stellar Lenses in the Black Hole Candidate Microlensing Events MACHO-96-BLG-5 and MACHO-98-BLG-6
Lu, Jessica R.; Abdurrahman, Fatima N.; Stephens, Haynes F.
Although stellar-mass black holes (BHs) are likely to be abundant in the Milky Way (N = 108-109), only 20 have been detected to date, all in accreting binary systems. Gravitational microlensing is a proposed technique to search for isolated BHs, which have not yet been detected. Two specific microlensing events, MACHO-1996-BL…
High-contrast and resolution near-infrared photometry of the core of R136
Langlois, Maud; Buckner, Anne S. M.; Khorrami, Zeinab +8 more
We present the sharpest and deepest near-infrared photometric analysis of the core of R136, a newly formed massive star cluster at the centre of the 30 Doradus star-forming region in the Large Magellanic Cloud. We used the extreme adaptive optics of the SPHERE focal instrument implemented on the ESO Very Large Telescope and operated in its IRDIS i…
A PPMAP analysis of the filamentary structures in Ophiuchus L1688 and L1689
Griffin, M. J.; Smith, M. W. L.; Marsh, K. A. +2 more
We use the Point Process MAPping (PPMAP) algorithm to reanalyse the Herschel and SCUBA-2 observations of the L1688 and L1689 subregions of the Ophiuchus molecular cloud. PPMAP delivers maps with high resolution (here 14 arcsec, corresponding to ${\sim}0.01\, {\rm pc}$ at ${\sim}140\, {\rm pc}$), by using the observations at their native resolution…
A Method to Extract Spatially Resolved Polycyclic Aromatic Hydrocarbon Emission from Spitzer Spectra: Application to M51
Ho, Luis C.; Xie, Yanxia; Zhang, Lulu
The mid-infrared spectrum contains rich diagnostics to probe the physical properties of galaxies, among which the pervasive emission features from polycyclic aromatic hydrocarbons (PAHs) offer promising means of estimating the star formation rate (SFR) relatively immune from dust extinction. This paper investigates the effectiveness of PAH emissio…
Resolved galactic superwinds reconstructed around their host galaxies at z > 3
Broadhurst, Tom; Chen, Hsiao-Wen; Rauch, Michael +2 more
This paper presents a detailed analysis of two giant Lyman-alpha (Ly α) arcs detected near galaxies at z = 3.038 and z = 3.754 lensed by the massive cluster MACS 1206-0847 (z = 0.44). The Ly α nebulae revealed in deep MUSE observations exhibit a double-peaked profile with a dominant red peak, indicating expansion/outflowing motions. One of the arc…
Standard stellar luminosities: what are typical and limiting accuracies in the era after Gaia?
Bakış, V.; Eker, Z.; Soydugan, F. +1 more
Methods of obtaining stellar luminosities (L) have been revised and a new concept, standard stellar luminosity, has been defined. In this paper, we study three methods: (i) a direct method from radii and effective temperatures; (ii) a method using a mass-luminosity relation (MLR); and (iii) a method requiring a bolometric correction. If the unique…
Two Populations of Carbon-enhanced Metal-poor Stars in the Disk System of the Milky Way
Yoon, Jinmi; Beers, Timothy C.; Lee, Young Sun +2 more
We present a chemodynamical analysis of low-resolution (R ~ 1300) spectroscopy of ~50,000 stars from the AAOmega Evolution of Galactic Structure survey, focusing on two key populations of (in total) 650 carbon-enhanced metal-poor (CEMP) stars within the disk system of the Milky Way: a mildly prograde population (Lz < 1000 kpc km s
Improved Measurements of Molecular Cloud Distances Based on Global Search
Wang, Hongchi; Xu, Ye; Su, Yang +5 more
The principle of the background-eliminated extinction-parallax (BEEP) method is examining the extinction difference between on- and off-cloud regions to reveal the extinction jump caused by molecular clouds, thereby revealing the distance in complex dust environments. The BEEP method requires high-quality images of molecular clouds and high-precis…
Chandra Observations of Excess Fe Kα Line Emission in Galaxies with High Star Formation Rates: X-Ray Reflection on Galaxy Scales?
Ricci, Claudio; Bauer, Franz E.; Hickox, Ryan C. +4 more
In active galactic nuclei (AGNs), fluorescent Fe Kα (iron) line emission is generally interpreted as originating from obscuring material around a supermassive black hole on the scale of a few parsecs. However, recent Chandra studies indicate the existence of iron line emission extending to kiloparsec scales in the host galaxy. The connection betwe…
First Observation of the Oxygen 630 nm Emission in the Martian Dayglow
Aoki, S.; Vandaele, A. C.; Daerden, F. +13 more
Following the recent detection of the oxygen green line airglow on Mars, we have improved the statistical analysis of the data recorded by the NOMAD/UVIS instrument on board the ExoMars Trace Gas Orbiter mission by summing up hundreds of spectra to increase the signal to noise ratio. This led to the observation of the OI 630 nm emission, the first…