Search Publications
On the Nature of the Small-scale Structure in the Cosmic Microwave Background Observed by PLANCK and WMAP
Verschuur, G. L.; Schmelz, J. T.
Small-scale features observed by Wilkinson Microwave Anisotropy Probe (WMAP) and PLANCK in the frequency range of 22-90 GHz show a nearly flat spectrum, which meets with expectations that they originate in the early universe. However, free-free emission from electrons in small angular scale galactic sources that suffer beam dilution very closely m…
Narrow-line X-Ray-selected Galaxies in the Chandra-COSMOS Field. II. Optically Elusive X-Ray AGNs
Civano, F.; Elvis, M.; Watson, M. G. +1 more
In the Chandra-COSMOS (C-COSMOS) survey, we have looked for X-ray-selected active galactic nuclei (AGNs), which are not detected as such in the optical, the so-called elusive AGNs. A previous study based on XMM-Newton and Sloan Digital Sky Survey observations has found a sample of 31 X-ray AGNs optically misclassified as star-forming (SF) galaxies…
Obliquities of Exoplanet Host Stars from Precise Distances and Stellar Angular Diameters
Quinn, Samuel N.; White, Russel J.
The next generation of exoplanet space photometry missions proposed by both NASA and ESA promise to discover small transiting planets around the nearest and brightest main-sequence stars. The physical and rotational properties of these stars, in conjunction with Gaia-precision distances, can be used to determine the inclination of the stellar rota…
On the Retrieval of Mesospheric Winds on Mars and Venus from Ground-based Observations at 10 µm
Lopez-Valverde, M. A.; Sornig, M.; Sonnabend, G. +1 more
A detailed analysis is presented of ground-based observations of atmospheric emissions on Mars and Venus under non-local thermodynamic equilibrium (non-LTE) conditions at high spectral resolution. Our first goal is to comprehend the difficulties behind the derivation of wind speeds from ground-based observations. A second goal is to set a framewor…
The X-Ray Zurich Environmental Study (X-ZENS). II. X-Ray Observations of the Diffuse Intragroup Medium in Galaxy Groups
Schawinski, Kevin; Finoguenov, Alexis; Silverman, John D. +4 more
We present the results of a pilot XMM-Newton and Chandra program aimed at studying the diffuse intragroup medium (IGM) of optically selected nearby groups from the Zurich ENvironmental Study (ZENS) catalog. The groups are in a narrow mass range about {10}13 {M}⊙ , a mass scale at which the interplay between the IGM and the gr…
Hot Plasma from Solar Active-Region Cores: Constraints from the Hinode X-Ray Telescope
Schmelz, J. T.; Christian, G. M.; Matheny, P. O.
Mechanisms invoked to heat the solar corona to millions of degrees kelvin involve either magnetic waves or magnetic reconnections. Turbulence in the convection zone produces MHD waves, which travel upward and dissipate. Photospheric motions continuously build up magnetic energy, which is released through magnetic reconnection. In this paper, we co…
Assessment of Models of Galactic Thermal Dust Emission Using COBE/FIRAS and COBE/DIRBE Observations
Kogut, A.; Odegard, N.; Chuss, D. T. +1 more
Accurate modeling of the spectrum of thermal dust emission at millimeter wavelengths is important for improving the accuracy of foreground subtraction for cosmic microwave background (CMB) measurements, for improving the accuracy with which the contributions of different foreground emission components can be determined, and for improving our under…
Spectroscopy from the Hubble Space Telescope Cosmic Origins Spectrograph of the Southern Nova-like BB Doradus in an Intermediate State
Szkody, Paula; Sion, Edward M.; Godon, Patrick +6 more
We present a spectral analysis of the spectrum from the Hubble Space Telescope Cosmic Origins Spectrograph (HST/COS) of the southern VY Scl nova-like variable BB Doradus, obtained as part of a Cycle 20 HST/COS survey of accreting white dwarfs (WDs) in cataclysmic variables. BB Dor was observed with COS during an intermediate state with a low mass …
Analysis of Co-spatial UV-optical HST/STIS Spectra of Planetary Nebula NGC 3242
Corradi, Romano L. M.; Balick, Bruce; Shaw, Richard A. +4 more
This project sought to consider two important aspects of the planetary nebula NGC 3242 using new long-slit HST/STIS spectra. First, we investigated whether this object is chemically homogeneous by spatially dividing the slit into different regions and calculating the abundances of each region. The major result is that the elements of He, C, O, and…
Long-term Study of the Double Pulsar J0737-3039 with XMM-Newton: Pulsar Timing
Tiengo, A.; Iacolina, M. N.; Pellizzoni, A. +8 more
The relativistic double neutron star binary PSR J0737-3039 shows clear evidence of orbital phase-dependent wind-companion interaction, both in radio and X-rays. In this paper, we present the results of timing analysis of PSR J0737-3039 performed during 2006 and 2011 XMM-Newton Large Programs that collected ∼20,000 X-ray counts from the system. We …