Search Publications
A New Visit to the Variable Stars in M56 and its Colour-Magnitude Diagram Structure
Arellano Ferro, A.; Deras, D.; Yepez, M. A. +1 more
We present a VI CCD photometric study and a membership analysis of the globular cluster M56 (NGC 6779). This produced a CMD decontaminated from field stars, which enabled a better confrontation with theoretical isochrones, zero-age horizontal branches (ZAHB) and post-ZAHB evolutionary tracks. Post He-flash evolutionary models with a He-core mass o…
The outer orbit of the high-mass stellar triple system Herschel 36 determined with the VLTI
Brandner, W.; Pott, J. -U.; Alberdi, A. +8 more
Multiplicity is a ubiquitous characteristic of massive stars. Multiple systems offer us a unique observational constraint on the formation of high-mass systems. Herschel 36 A is a massive triple system composed of a close binary (Ab1-Ab2) and an outer component (Aa). We measured the orbital motion of the outer component of Herschel 36 A using infr…
Updates to the SUMER Spectral Atlas
Wilhelm, Klaus; Schühle, Udo; Curdt, Werner +3 more
We present a reworked version of the SUMER spectral atlas (Curdt et al., 2001). New identifications are given for more than 100 emission lines; entries were corrected or added to the list. The solar emission curve - spectral radiance versus wavelength - in the SUMER spectral range is now available in digital format as electronic supplementary mate…
Study of UV bright sources in globular cluster NGC 4590 using Ultraviolet Imaging Telescope (UVIT) observations
Pradhan, Ananta C.; Mohapatra, Abhisek; Parthasarathy, M. +5 more
We have studied ultraviolet (UV) bright sources in the Galactic globular cluster (GGC) NGC 4590 using Ultraviolet Imaging Telescope onboard the AstroSat satellite. Using UV-optical colour-magnitude diagrams (CMDs), we have identified and characterized the sources of different evolutionary stages i.e. blue horizontal branch stars (BHBs), extremely …
Magnetic fields and young stellar objects in cometary cloud L1616
Soam, Archana; Saha, Piyali; Gopinathan, Maheswar +3 more
The Lynds' Dark Nebula (LDN) 1615/1616 and CB 28 (hereafter L1616) together form a cometary globule located at an angular distance of about 8° west of the Orion OB1 association, aligned roughly along the east-west direction, and showing a distinct head-tail structure. The presence of massive stars in the Orion belt has been considered to be respon…
Variable Star Population in the Open Cluster NGC 6819 Observed by the Kepler Spacecraft
Németh, P.; Baran, A. S.; Sanjayan, S. +1 more
We present the list of variable stars we found in the Kepler superstamp data covering approximately nine arcminutes from the central region of NGC 6819. This is a continuation of our earlier work. We classified the variable stars based on the variability type and we established their cluster membership based on the available Gaia Data Release 3 as…
The MICROSCOPE space mission: the first test of the equivalence principle in a space laboratory
Bergé, Joel; Chhun, Ratana; Métris, Gilles +4 more
This paper introduces the current special issue focussed on the MICROSCOPE mission. This mission is the first experimental test in space of the weak equivalence principle (WEP) using man-made test-masses-as opposed to astronomical tests-with the goal to reach a precision two orders of magnitude better than ground-based experiments. Selected in 199…
Cool interstellar medium as an evolutionary tracer in ALMA-observed local dusty early-type galaxies
Popescu, Cristina C.; Davis, Timothy A.; Sansom, Anne E. +1 more
The content and distribution of cool interstellar medium (<30 K) can indicate the evolutionary mechanisms that transform late-type to early-type galaxies (ETGs). To investigate this, ALMA observations of 12CO[2-1] line emission were obtained for five dusty ETGs from a complete sample in low-density environments. Four of the ETGs have…
Prominence instability and CMEs triggered by massive coronal rain in the solar atmosphere
Hanslmeier, A.; Gömöry, P.; Zaqarashvili, T. V. +3 more
Context. The triggering process for prominence instability and consequent coronal mass ejections (CMEs) is not fully understood. Prominences are maintained by the Lorentz force against the gravity; therefore, reduction of the prominence mass due to the coronal rain may cause the change of the force balance and hence destabilisation of the structur…
Blackbody Temperature of 200+ Stellar Flares Observed with the CoRoT Satellite
Rabello Soares, M. Cristina; de Freitas, Marcia C.; Ferreira, Bernardo P. L.
We estimated blackbody temperature for 209 flares observed at 69 F-K stars, significantly increasing the number of flare temperature determinations. We used the Blue and Red channels obtained by the 27 cm telescope of the CoRoT satellite at high cadence and long duration. The wavelength limits of the channels were estimated using spectra from the …