Search Publications
A Joint NICER and XMM-Newton View of the “Magnificent” Thermally Emitting X-Ray Isolated Neutron Star RX J1605.3+3249
Enoto, Teruaki; Bogdanov, Slavko; Ray, Paul S. +11 more
Thermally emitting X-ray isolated neutron stars (NSs) represent excellent targets for testing cooling surface emission and atmosphere models, which are used to infer the physical parameters of the NS. Among the seven known members of this class, RX J1605.3+3249 is the only one that still lacks confirmation of its spin period. Here we analyze NICER…
Solar Active Region Heating Diagnostics from High-temperature Emission Using the MaGIXS
Golub, Leon; Winebarger, Amy R.; Warren, Harry P. +7 more
The relative amount of high-temperature plasma has been found to be a useful diagnostic to determine the frequency of coronal heating on sub-resolution structures. When the loops are infrequently heated, a broad emission measure (EM) over a wider range of temperatures is expected. A narrower EM is expected for high-frequency heating where the loop…
Gaia DR2 orbital properties for field stars with globular cluster-like CN band strengths
Posti, L.; Savino, A.
Context. Large spectroscopic surveys of the Milky Way have revealed that a small population of stars in the halo have light element abundances comparable to those found in globular clusters. The favoured explanation for the peculiar abundances of these stars is that they originated inside a globular cluster and were subsequently lost.
Aims: U…
Hemispheric asymmetry in meridional flow and the sunspot cycle
Antia, H. M.; Nandy, Dibyendu; Lekshmi, B.
Magnetohydrodynamic dynamo modelling shows that the large-scale solar meridional plasma flow plays an important role in governing the dynamics of the sunspot cycle. Observations indicate that meridional flow velocities at each solar latitude and depth vary over time and are asymmetric across the equator. Here, using helioseismic observations we ex…
Monitoring the Superorbital Period Variation and Spin Period Evolution of SMC X-1
Enoto, Teruaki; Ueda, Yoshihiro; Hu, Chin-Ping +2 more
The X-ray pulsar SMC X-1 shows a superorbital modulation with an unstable cycle length in the X-ray band. We present its timing behaviors, including the spin, orbital, and superorbital modulations, beyond the end of the Rossi X-ray Timing Explorer mission. The time-frequency maps derived by the wavelet Z-transform and the Hilbert-Huang transform s…
Hubble Space Telescope Spectroscopy of a Planetary Nebula in an M31 Open Cluster: Hot-bottom Burning at 3.4 M ⊙
Bond, Howard E.; Ciardullo, Robin; Jacoby, George H. +1 more
We use imaging and spectroscopy from the Hubble Space Telescope (HST) to examine the properties of a bright planetary nebula (PN) projected within M31's young open cluster B477-D075. We show that the probability of a chance superposition of the PN on the cluster is small, ≲2%. Moreover, the radial velocity of the PN is the same as that of the clus…
A comparison between the two lobes of comet 67P/Churyumov-Gerasimenko based on D/H ratios in H2O measured with the Rosetta/ROSINA DFMS
De Keyser, Johan; Hansen, Kenneth C.; Gombosi, Tamas I. +13 more
The nucleus of the Jupiter-family comet 67P/Churyumov-Gerasimenko was discovered to be bi-lobate in shape when the European Space Agency spacecraft Rosetta first approached it in 2014 July. The bi-lobate structure of the cometary nucleus has led to much discussion regarding the possible manner of its formation and on how the composition of each lo…
Radio emission from interstellar shocks: Young type Ia supernova remnants and the case of N 103B in the Large Magellanic Cloud
Haberl, F.; Filipović, M. D.; Rowell, G. +19 more
We investigate young type Ia supernova remnants (SNRs) in our Galaxy and neighbouring galaxies in order to understand their properties and early stage of their evolution. Here we present a radio continuum study based on new and archival data from the Australia Telescope Compact Array (ATCA) towards N 103B, a young (≤1000 yrs) spectroscopically con…
A stellar occultation by Vanth, a satellite of (90482) Orcus
Bosh, A. S.; Lister, T. A.; Schindler, K. +5 more
A stellar occultation by the large trans-Neptunian object (90482) Orcus was predicted to occur on 2017 March 07. Observations were made at five sites in North and South America: the 0.6-m Astronomical Telescope of the University of Stuttgart (ATUS) at Sierra Remote Observatories, California; Las Cumbres Observatory's 1-m telescope at McDonald Obse…
UVIT-HST-GAIA view of NGC 288: a census of the hot stellar population and its properties from UV
Rao, N. Kameswara; Stetson, Peter B.; Sahu, Snehalata +2 more
A complete census of the blue horizontal branch (BHB) and blue straggler star (BSS) population within a 10' radius from the centre of the globular cluster NGC 288 is presented, based on images from the Ultraviolet Imaging Telescope (UVIT). The UV and UV-optical colour-magnitude diagrams (CMDs) are constructed by combining the UVIT, HST-ACS and gro…