inaoe.edu.mx
INAOE | Astrofísica | Seminarios
Asignar puntaje:
 
Periodo Año:

   
2015-01-16 Synthetic Observations & Analysis of Spectral Line Data
Area:
Investigador Invitado Robert John Loughnane
Filiación Institucional
Resumen: Ver resumen In this contribution, I will discuss my work in creating synthetic spectra for specific time-steps along the formation of a protostellar core considering different initial conditions. Synthetic spectra are created for optically thick molecular transitions such as HCO+ J=1-0 and NH3 (1,1) due to their moderate critical densities (relative to typical molecular cloud volume densities), which allows the detection of such transitions far from the perceived core centre. In the case of NH3 (1,1), we have included the underlying magnetic hyperfine structure components so that we are able to test the hypotheis presented by Pineda et al. (2010) termed the "transition to coherence" whereby the intrinsic hyperfine components begin to emerge once the turbulent motions of the core gas subside close to the core centre with the inward motions becoming more coherent. I will also discuss the theory underpinning a spectral data analysis routine called COLHYPOD to which I am contributing to.
   
Lugar-Hora - 12:00
   
2015-01-23 The evolution of galaxies in compact groups over the past 3 Gyr
Area:
Investigador Invitado Theodoros Bitsakis
Filiación Institucional IA-UNAM
Resumen: Ver resumen We present the study of the evolution of the star formation and the nuclear acitivity in compact groups of galaxies over the past 3 Gyr. Our analysis is based on the largest multi-wavelength compact group sample to-date, containing complete UV-to-IR photometry for 1,770 groups (7,417 galaxies). We classify the nuclear activity of the galaxies based on optical emission line and mid-IR diagnostic classifications and estimate the physical properties of the galaxies using theoretical spectral energy distribution modeling. Concering the nuclear activities, we observe a singificant increase of the number of the AGN-hosting galaxies as we are moving towards lower redshifts, and we report the almost complete absence of Seyfert 1 nuclei. On the other hand, we observe a singificant "reddening" of the UV-optical colours of the galaxies and a decrease of their specific star formation rates, caused by both the reduction of their star formation rates as well as the build-up of their stellar masses, over the past 3 Gyr. Our results suggest that the depletion of gas, due to past star formation and/or tidal stripping is the major mechanism driving the evolution of the star formation and nuclear activity in compact groups.
   
Lugar-Hora - 12:00
   
2015-01-30
Area:
Investigador Invitado Victor de la Luz
Filiación Institucional UNAM
Resumen: Ver resumen
   
Lugar-Hora Auditorio de Docencia - 12:00
   
2015-02-06 On the road to precision cosmology via high redshift burst of star formation
Area:
Investigador Invitado
Filiación Institucional INAOE
Resumen: Ver resumen We used the L(Hbeta) -sigma distance estimator based on the correlation between the ionised gas velocity dispersion and Balmer emission line luminosities of HII Galaxies and Giant H II regions to trace the expansion of the Universe up to z - 2.33. This approach provides an independent constraint on the equation of state of dark energy and its possible evolution with cosmic time.

We have used Very Large Telescope and Subaru high-dispersion spectroscopic observations of a local sample of H II galaxies, identified in the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) catalogue in order to redefine and improve the L(Hbeta) - sigma distance indicator and to determine the Hubble constant. To this end, we utilized as local calibration or 'anchor' of this correlation GEHR in nearby galaxies which have accurate distance measurements determined via primary indicators. Using our best sample of 69 nearby H II galaxies and 23 GEHR in nine galaxies, we obtain H0 = 74.3 +/- 3.1 (statistical) +/-2.9 (systematic)kms-1 Mpc-1.

We present high-dispersion spectroscopy of HII galaxies at redshifts between 0.6 and 2.33, obtained at the VLT using XShooter. Using six of these HII galaxies we obtain broad constraints on the plane Omega_m - w0. The addition of 19 high-z HII galaxies from the literature improves the constraints and highlights the need for high quality emission line profiles, fluxes and reddening corrections. The 25 high-z HII galaxies plus our local compilation of 107 H II galaxies up to z = 0.16 were used to impose further constraints. Our results are consistent with recent studies, although weaker due to the as yet small sample and low quality of the literature data of high-z HII galaxies.

We show that much better and competitive constraints can be obtained using a
larger sample of high redshift HII galaxies with high quality data that can be easily
obtained with present facilities like KMOS at the VLT.
   
Lugar-Hora - 12:00
   
2015-02-13 FILEC
Area: tbd
Investigador Invitado FILEC
Filiación Institucional INAOE
Resumen: Ver resumen tbd
   
Lugar-Hora - 12:00
   
2015-02-17 How supermassive black holes produce jets: recent insights from radio polarimetry
Area:
Investigador Invitado
Filiación Institucional IA-UNAM
Resumen: Ver resumen Powerful relativistic jets in radio-loud active galactic nuclei (AGN) can deposit enormous
amounts of mechanical energy into their surroundings, potentially regulating
star-formation in the host galaxy and the fuel supply back onto the supermassive black hole.
Substantial progress in our understanding of AGN jets has been made in recent times,
particularly in relation to the conditions required for efficient jet formation, as well as our
knowledge of the three-dimensional magnetic field structure of the jet. I will review
our current understanding of AGN jets before presenting new radio polarization and Faraday
rotation observations of radio-loud AGN from parsec to kiloparsec scales. I will show
the importance of full-Stokes, broadband radio observations in providing important
constraints on fundamental jet parameters such as the jet magnetic field strength, it's 3D
structure, and the amount of magnetic flux at the jet launching site.
   
Lugar-Hora - 12:00
   
2015-03-13 Are there ultramassive black holes out there?
Area:
Investigador Invitado
Filiación Institucional INAOE
Resumen: Ver resumen We have recently discovered that Holm 15A, the brightest cluster galaxy in Abell 85 (A85-BCG), could host an ultramassive black hole (UMBH) with a mass of about one hundred billion solar masses. This large black hole mass results from extrapolations of black hole mass scaling laws with host galaxy estructure and dynamics. We review known scaling laws and discuss the existence of UMBH in the universe. We also comment on the likely effects of UMBH on galaxy formation and evolution.
   
Lugar-Hora - 12:00
   
2015-03-20 Binariedad y el problema de la discrepancia de abundancias en nebulosas planetarias
Area:
Investigador Invitado
Filiación Institucional
Resumen: Ver resumen
   
Lugar-Hora - 12:00
   
2015-03-25 The search for the highest energy gamma-ray emission from pulsars with Fermi and HAWC
Area:
Investigador Invitado Pablo Saz-Parkinson
Filiación Institucional Universidad de California Santa Cruz
Resumen: Ver resumen The launch of the Fermi satellite in 2008 has led to an explosion in our knowledge of
gamma-ray pulsars above 100 MeV, with over 150 pulsars now detected in this energy range.
Twenty-eight pulsars have been detected by the Fermi Large Area Telescope (LAT) above 10 GeV and 13 of these show
pulsations at even higher energies (> 25 GeV). Meanwhile, ground-based Imaging Atomospheric
Cherenkov Telescopes (IACTs: H.E.S.S., MAGIC, and VERITAS) have reported emission above 50 GeV
from 2 pulsars (the Crab and Vela), with the latest results from MAGIC suggesting that the Crab pulsar emits
pulsations above 1 TeV. I will discuss a search for high-energy emission LAT-detected gamma-ray pulsars using the latest Fermi
LAT data and outline a project to use the recently-inaugurated HAWC observatory to carry out a survey of the very high
energy (VHE, > 100 GeV) sky to search for pulsations from gamma-ray pulsars in the Northern Hemisphere.
   
Lugar-Hora - 12:00
   
2015-04-03 Easter
Area:
Investigador Invitado Easter
Filiación Institucional INAOE
Resumen: Ver resumen tbd
   
Lugar-Hora - 12:00
   
2015-04-10 The Herschel spectral surveys of star-forming regions: The interstellar shock
Area:
Investigador Invitado Arturo Gomez-Ruiz
Filiación Institucional INAOE
Resumen: Ver resumen
   
Lugar-Hora - 12:00
   
2015-04-17
Area:
Investigador Invitado
Filiación Institucional INAOE
Resumen: Ver resumen
   
Lugar-Hora Auditorio Docente - 12:00


Última modificación :
05-07-2010 a las 14:08 por Webmaster

Dirección: Luis Enrique Erro # 1, Tonantzintla, Puebla, México C.P. 72840 | Tel: (222) 266.31.00 Ext: 1324 y 1325 | Contacto: astrofi@inaoep.mx | Fax: 247.22.31

 

Esta obra está licenciada bajo una Licencia Creative Commons Atribución-No Comercial-Sin Obras Derivadas 2.5 México

Creative Commons License