Seminar Notes

Wednesday Seminar 11-8-2006

Shedding Quasar light on optically thick absorption line systems

by Joseph Hennawi (U.C. Berkeley)

Theh physical problemis a quasar illuminating an optically thick cloud of H I is very simple compared to other problems in galaxy formations.

tau = tau(0)*e^-(x^2)/2

x = (delta v/v) / (sigma/c)

- Photons only escape from tails of velocity distribution where tau_lyalpha is small LLSs 'reflect' ~ 60% of UV radiation in a fluorescent double peaked line.

- double peaked lines

SD_Lyapha = 3.7*10^-20 * (J[912]/[-22]/4)*((1+z)/4)^-4 ergs cm-2s-1 or mu_Lyalpha = 30 mag

LOS - line of sight

question I had, "how do we know that this is surviving?"

Wednesday Seminar 11-1-2006

Frazer Own

NRAO

Collaborates with UCSD people: Lonsdale, Smith, Polletta

Terms to look up: AGN and Massive SF

ULIRG microJy radio sources are large ~ 10kpc

EVLA will give science in 2009

Wednesday Seminar 10-4-2006

Nissim Kanekar

National Radio Astronomy Observatory, Socorro

Uzan… 2003, Rev. Mod. Phys

Alpha dot tests local incariance and equivalence principle
Gotta look at dimensionless constants


Values for delta alpha/alpha

0.86 x 10^-3 Chand 2005, A&A

-0.54 +- 0.12 * 10^-5 Murphy 2003, MNRAS

0.06 +- 0.06 * 10^-5 Srianand 2004, Phys Rev. Letters

0.02 +- 0.21 * 10 ^ -5 Murphy 2006, PSA conference

delta mu/mu = 12.0 +- 0.6 * 10 ^ -5 Reinhold 2006, Phys Rev. Lett.
current theories relates delta mu/mu to be about 40 times as strong as delta alpha /alpha


Nissim looks at Radio OH lines

multiple transitions, 4 lines in ground state

there are 2 physical effects:

Lambda - Doubling & hyperfine splitting

Different dependencies on alpha, mu, gp.. !!

d a/a = 0.6 +- 1 * 10^ -5

Amplitudes, widths agree, .45 +- .18 * 10 ^ -5

Delta G/G = ( -2.09 +- 0.92 ) * 10 ^ -5
da/a = -.56 +- .25 10-5
dmu/mu = 1.12+- 0.50 10-5

Within 2 sigma:

These results not as serious:
delta a/a < 0.67 10-5

dmu/mu < 1.35 * 19-5 for 0 < z < 0.7

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