Search Publications
One-dimensional Modeling for Temperature-dependent Upflow in the Dimming Region Observed by Hinode/EUV Imaging Spectrometer
Shimizu, T.; Hara, H.; Watanabe, T. +4 more
We previously found a temperature-dependent upflow in the dimming region following a coronal mass ejection observed by the Hinode EUV Imaging Spectrometer (EIS). In this paper, we reanalyzed the observations along with previous work on this event and provided boundary conditions for modeling. We found that the intensity in the dimming region drama…
Testing a Scale-independent Method to Measure the Mass of Black Holes
Titarchuk, L.; Satyapal, S.; Gliozzi, M. +2 more
Estimating the black hole mass at the center of galaxies is a fundamental step not only for understanding the physics of accretion, but also for the cosmological evolution of galaxies. Recently, a new method, based solely on X-ray data, was successfully applied to determine the black hole mass in Galactic systems. Since X-rays are thought to be pr…
On the Spin-down and Magnetic Field of the X-ray Pulsar 1E 1207.4-5209
Gotthelf, E. V.; Halpern, J. P.
We analyze all of the archival X-ray timing data from the years 2000-2008 on the weakly magnetized central compact object (CCO) pulsar 1E 1207.4-5209 in an attempt to measure its dipole magnetic field strength via spin-down. because most of these observations were not planned for the purpose of phase-coherent timing, the resulting ephemeris is not…
Fokker-Planck Models for M15 Without a Central Black Hole: The Role of the Mass Function
Cohn, Haldan N.; Lugger, Phyllis M.; Murphy, Brian W.
We have developed a set of dynamically evolving Fokker-Planck models for the collapsed-core globular star cluster M15, which directly address the issue of whether a central black hole is required to fit Hubble Space Telescope (HST) observations of the stellar spatial distribution and kinematics. As in our previous work reported by Dull et al., we …
Disentangling the Environment of the FU Orionis Candidate HBC 722 with Herschel
Henning, Thomas; Skinner, Stephen L.; Güdel, Manuel +16 more
We analyze the submillimeter emission surrounding the new FU Orionis-type object, HBC 722. We present the first epoch of observations of the active environs of HBC 722, with imaging and spectroscopy from PACS, SPIRE, and HIFI on board the Herschel Space Observatory, as well as CO J = 2-1 and 350 µm imaging (SHARC-II) with the Caltech Submill…
A Droplet Model of Quiescent Prominence Downflows
Berger, T.; Haerendel, G.
Observations of quiescent prominences with the Solar Optical Telescope on the Hinode satellite have revealed the ubiquitous existence of downflows forming coherent thin and highly structured vertically oriented threads with velocities between 10 and 20 km s-1. Their widths range between 300 and 500 km. They are often initiated at the to…
Super-Chandrasekhar SNe Ia Strongly Prefer Metal-poor Environments
Stanek, K. Z.; Prieto, J. L.; Stoll, R. +1 more
We discuss the emerging trend that super-Chandrasekhar Type Ia Supernovae (SCSNe) with progenitor mass estimates significantly exceeding ~1.4 M sun tend to explode in metal-poor environments. While Taubenberger et al. noted that some of the SCSNe host galaxies are relatively metal-poor, we focus quantitatively on their locations in the …
Comparison Between Observation and Simulation of Magnetic Field Changes Associated with Flares
Jing, Ju; Wang, Haimin; Fan, Yuhong +1 more
It has been a long-standing question in solar physics how magnetic field structure changes with eruptive events (e.g., flares and coronal mass ejections). In this Letter, we present the eruption-associated changes in the magnetic inclination angle, the horizontal component of magnetic field vectors, and the Lorentz force. The analysis is based on …
Probing the Star Formation History and Initial Mass Function of the z ~ 2.5 Lensed Galaxy SMM J163554.2+661225 with Herschel
Papovich, Casey; Finkelstein, Steven L.; Egami, Eiichi +6 more
We present the analysis of Herschel Spectral and Photometric Imaging Receiver far-infrared (FIR) observations of the z = 2.515 lensed galaxy SMM J163554.2+661225. Combining new 250, 350, and 500 µm observations with existing data, we make an improved fit to the FIR spectral energy distribution of this galaxy. We find a total infrared (IR) lu…
Direct Measurements of Magnetic Twist in the Solar Corona
Longcope, D. W.; Malanushenko, A.; Yusuf, M. H.
In the present work, we study the evolution of magnetic helicity in the solar corona. We compare the rate of change of a quantity related to the magnetic helicity in the corona to the flux of magnetic helicity through the photosphere and find that the two rates are similar. This gives observational evidence that helicity flux across the photospher…