BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//talks.cam.ac.uk//v3//EN
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
TZNAME:BST
DTSTART:19700329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
TZNAME:GMT
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CATEGORIES:Galaxies Discussion Group
SUMMARY:Probing Cosmic Dawn with the most distant galaxies
  - Nicolas Laporte (Cavendish)
DTSTART;TZID=Europe/London:20200529T113000
DTEND;TZID=Europe/London:20200529T123000
UID:TALK142237AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/142237
DESCRIPTION:One of the key question of modern extragalactic as
 tronomy is to determine when the first generation 
 of stars and galaxies started to bathe the Univers
 e in light. According to the most recent simulatio
 ns\, this "Cosmic Dawn" occurred ~200 Myr after th
 e Big-Bang (corresponding to a redshift of z~20). 
 The recent claim of the detection of a redshifted 
 21cm absorption in the CMB suggests that the forma
 tion of the first generation of stars and galaxies
  happened at z~17.  However\, observing these gala
 xies at very high-redshift (z>11) is well beyond t
 he capabilities of current ground-based and space 
 instruments. However recently high-redshift galaxi
 es discovered at fascinating distances  z>8\,  wer
 e interpreted  in terms of ages and intense star f
 ormation histories. These galaxies are revealed ma
 ture with ages of 500 million years\, starting jus
 t after the Big-Bang. Such early systems with sign
 ificant stellar masses and star formation rates wh
 ich decline with time are not easily reproduced by
  contemporary numerical simulations. The physics o
 f these galaxies (mass growth\, dissipation by ion
 izing energy\, gas and electronic densities) are t
 he main objectives\, to be related to dark matter 
 haloes and to the growth of supermassive black hol
 es. In this talk I will review the latest results 
 on the search for and study of the most distant so
 urces\, in terms of physical properties (age\, SFR
 \, stellar mass\, dust mass) and on their contribu
 tion to the reionisation budget. 
LOCATION:via zoom 
CONTACT:Martin Haehnelt
END:VEVENT
END:VCALENDAR