Search Publications
Broad-band analysis of X-ray pulsar 2S 1845-024
Tsygankov, Sergey S.; Lutovinov, Alexander A.; Poutanen, Juri +4 more
We present the results of a detailed investigation of the poorly studied X-ray pulsar 2S 1845−024 based on data obtained at the NuSTAR observatory during the type I outburst in 2017. Neither pulse phase-averaged nor phase-resolved spectra of the source show evidence for a cyclotron absorption feature. We also used data obtained from other X-ray ob…
Deep V and I CCD photometry of young star cluster NGC 1893 with the 3.6m DOT
Pandey, S. B.; Panwar, Neelam; Kumar, Amit
Young star clusters consisting of massive stars are the ideal sites to study the star formation processes and influence of massive stars on the subsequent star formation. NGC 1893 is a young star cluster associated with the HII region Sh2-236. It contains about five 'O'-type stars and several early 'B'-type stars. It is located at a moderate dista…
The eROSITA extragalactic CalPV serendipitous catalog
Maitra, Chandreyee; Nandra, Kirpal; Reiprich, Thomas H. +22 more
Context. The eROSITA X-ray telescope on board the Spectrum-Roentgen-Gamma (SRG) observatory performed calibration and performance verification (CalPV) observations between September 2019 and December 2019, ahead of the planned 4-yr all-sky surveys. Most of them were deep, pointing-mode observations.
Aims: We present here the X-ray catalog det…
Unveiling the formation of NGC 2915 with MUSE: A counter-rotating stellar disk embedded in a disordered gaseous environment
Lin, Zesen; Chen, Guangwen; Kong, Xu +6 more
NGC 2915 is a unique nearby galaxy that is classified as an isolated blue compact dwarf based on its optical appearance but has an extremely extended H I gas disk with prominent Sd-type spiral arms. To unveil the starburst-triggering mystery of NGC 2915, we performed a comprehensive analysis of deep VLT/MUSE integral field spectroscopic observatio…
On the precision of full-spectrum fitting of simple stellar populations - IV. A systematic comparison with results from colour-magnitude diagrams
Goudfrooij, Paul; Asa'd, Randa; As'ad, A. M.
In this fourth paper of a series on the precision of ages of stellar populations obtained through the full-spectrum fitting technique, we present a first systematic analysis that compares the age, metallicity, and reddening of star clusters obtained from resolved and unresolved data [namely colour-magnitude diagrams (CMDs) and integrated-light spe…
Constraining leptonic emission scenarios for the PeVatron candidate HESS J1702−420 with deep XMM-Newton observations
Khélifi, B.; Lemière, A.; Terrier, R. +3 more
Aims: We aim to search for a hidden leptonic accelerator, such as a high-Ė pulsar, associated with the unidentified TeV object HESS J1702−420A.
Methods: We carried out a 72 ks X-ray observation with the XMM-Newton satellite and analyzed the resulting data jointly with the publicly available HESS spectral energy distribution (SED) results…
Photometric Investigation of Contact Binary DY Cet Based on TESS Data
Yıldırım, M. F.
We present a photometric analysis of the Transiting Exoplanet Survey Satellite (TESS) light curve of contact binary system DY Cet and the behavior of its orbital period variation. The light curve and published radial velocity data analysis was performed using the Wilson-Devinney code. As a result of simultaneous analysis of the light curve with ra…
Effects from dayside magnetosphere to distant tail unleashed by a bifurcated, non-reconnecting interplanetary current sheet
Berchem, J.; Wing, S.; Farrugia, C. J. +6 more
Global magnetospheric effects resulting from the passage at Earth of large-scale structures have been well studied. The effects of common and short-term features, such as discontinuities and current sheets (CSs), have not been studied in the same depth. Herein we show how a seemingly unremarkable interplanetary feature can cause widespread effects…
Gas inflows in the polar ring of NGC 4111: the birth of an AGN
Lützgendorf, Nora; Ma, Chung-Pei; Gebhardt, Karl +14 more
We have used Hubble Space Telescope (HST) images, SAURON Integral Field Spectroscopy (IFS), and adaptative optics assisted Gemini NIFS near-infrared K-band IFS to map the stellar and gas distribution, excitation and kinematics of the inner few kpc of the nearby edge-on S0 galaxy NGC 4111. The HST images map its ≈450 pc diameter dusty polar ring, w…
Interaction of convective plasma and small-scale magnetic fields in the lower solar atmosphere
Utz, Dominik; Vargas Domínguez, Santiago
In the following short review we will outline some of the possible interaction processes of lower solar atmospheric plasma with the embedded small-scale solar magnetic fields. After introducing the topic, important types of small-scale solar magnetic field elements are outlined to then focus on their creation and evolution, and finally end up desc…