Events

We run a regular programme of seminars for staff and students.

Speaker Seminar Details

Dr. Jan Forbrich (University of Hertfordshire)

(Colloquium) The Orion Radio All-Stars: new perspectives in stellar radio astronomy

With significant new observing capabilities, centimeter-wavelength radio astronomy is currently in a renaissance leading up to the advent of the Square Kilometre Array (SKA). The sensitivity upgrades of both the NRAO Very Large Array (VLA) and the Very Long Baseline Array (VLBA) have begun to provide us with a much improved perspective on stellar centimeter radio emission, particularly concerning young stellar objects (YSOs) and ultracool dwarfs. For the first time we now have systematic access to the radio time domain. I will mainly present a deep VLA and VLBA radio survey of the Orion Nebula Cluster (ONC), where we have found hundreds of compact radio sources, a sevenfold increase over previous studies, and intricate detail on the radio emission of proplyds. We can now better disentangle thermal and nonthermal radio emission by assessing spectral indices, polarization, variability, and brightness temperatures (VLBA). With simultaneous radio-X-ray time domain information (Chandra), this project is providing first constraints on YSO radio flares and their relation with X-ray flares, as well as improved constraints on the overall high-energy irradiation of their surroundings, including protoplanetary disks. Our astrometric VLBA follow-up of the ONC radio stars is now in full swing. I will thus additionally discuss the use of the VLBA for precision stellar astrometry in the Gaia era, highlighting how VLBI astrometry is allowing us to extend the Gaia sample of YSOs and ultracool dwarfs by including embedded objects, distant obscured sources in the Galactic plane, and faint ultracool dwarfs, while providing important opportunities for astrometric cross-calibration.

17 January 2018 (15:00)
Queens Buildings N/3.28

Dr. Claudia Cicone (Brera Observatory, Milan)

(Astronomy Seminar) The multiphase nature of outflows in AGN host galaxies

Galactic outflows have a multiphase nature, as evidenced by observations and expected by theoretical works. In particular, observations of extremely massive and fast molecular outflows have shown that AGNs and powerful starbursts can undermine even the coldest and densest phase of the ISM, which is the fuel for star formation. A significant boost of the molecular outflow mass-loss rate compared to the SFR is observed in galaxies whose bolometric luminosity is dominated by an AGN, suggesting that the molecular gas component encloses key information about the radiative-mode AGN feedback mechanism. In this seminar I will review and discuss current observational work on multiphase outflows in AGN host galaxies, with a special focus on recent results on molecular outflows.

24 January 2018 (14:00)
Queens Buildings N/3.28

Dr. Alvaro Hacar (Universiteit Leiden)

(Astronomy Seminar) TBD

31 January 2018 (14:00)
Queens Buildings N/3.28

Dr. Camilla Danielski (Observatoire de Paris)

(Astronomy Seminar) TBD

7 February 2018 (14:00)
Queens Buildings N/3.28

Prof. Stefan Hild (University of Glasgow)

(Astronomy Seminar) TBD

TBD

28 February 2018 (14:00)
Queens Buildings N/3.28

Dr. Michela Mapelli (INAF - Osservatorio Astronomico di Padova)

(Astronomy Seminar) TBD

TBD

7 March 2018 (14:00)
Queens Buildings N/3.28

Dr. Antonio Chrysostomou (SKA Organization)

(Colloquium) TBD

TBD

14 March 2018 (15:00)
Queens Buildings N/3.28