Monday Seminar Hannah Zohren

/Monday Seminar Hannah Zohren

Monday Seminar Hannah Zohren

Event Details

IMPRS talk by Hannah Zohren, Chair: Ivana

Title: Galaxy Clusters – Weak Lensing Mass Constraints
Galaxy clusters provide a versatile basis for studies of the cosmological parameters that govern the Universe. Detections based on the Sunyaev Zel’dovich (SZ) effect allow us to find clusters at very high redshift. These enable astrophysical and cosmological investigations that can expand on our current knowledge from lower redshift.

In my talk, I will briefly outline our strategy to obtain HST based weak lensing mass estimates for the 9 high redshift clusters (z>1.2) with the highest SZ-significance in the 2500 deg2 SPT-SZ Survey. I will particularly focus on the aspect of a proper source selection in order to distinguish the background galaxies which carry the weak lensing signal from the foreground and cluster galaxies which dilute the signal if they are not removed from the measurements.

Talk by Nordia-Jazmin Ordonez-Toro, University of Guanajuato (UG), Mexico

Title: Astrometric studies of binary young stellar objects using VLBI.

Studying binary and multiple stars require observations with high angular resolution and high astrometric accuracy, for this, the Gaia satellite provides orbital parameters when the stars have a separation above 0.1 arc-seconds, but Systems with smaller separations need to be studied with techniques that provide higher angular resolution observations, because the models seem to underestimate the masses of these systems.
The Very Long Baseline Array (VLBA) provides angular resolutions around 0.001 arc-seconds and better astrometric precisions, it is ideal to study this type of star systems, therefore the observation with VLBI allows us to determine the dynamical masses of YSOs in different star forming regions by using the Very Long Baseline Interferometry technique. The resulting masses will be used to test evolutionary models of YSOs.

Talk by Vanessa Yanza-Lopez, University of Guanajuato, Mexico

Title: Identification and classification of compact radio sources in M17 region with VLA observations.

At radio wavelengths we can detect different emission mechanism of celestial objects, such as thermal emission and non thermal emission. In particular, in HII regions is important to know what is the emission mechanism of the compact sources because allow us to know: Which sources belong or not to the region?, What role do these compact sources play in the region itself?, What is the type of emission mechanism that dominates? So in this work, I’m studying the compact sources in an specific region, the M17 region, that is a giant molecular cloud relatively close to through VLA observations.