Title: Exploiting the Forthcoming Pan-STARRS Dataset
Speaker: Yan-Chuan Cai
Institution: University of Durham, UK
Abstract: Pan-STARRS (Panoramic Survey Telescope and Rapid Response
System) 3pi survey will cover 3/4 of the sky. Its PS1 telescope is
expected to detect approximately 23rd magnitude in less than a week.
For using the forthcoming Pan-STARRS data to study Large Scale
Structure, we have used the Millennium N-body simulation and the
GALFORM semi-analytical galaxy formation model to build a mock
Pan-STARRS galaxy catalogue. This allows us to determine the basic
properties expected for the Pan-STARRS surveys, such as the number
counts of galaxies and their redshift distribution. These mocks have
been produced for use by the Pan-STARRS consortium to test the
performance of photometric redshift estimation codes. Applications
of this work such as impact of photo-z errors on the measurement of
baryonic acoustic oscillations will be addressed.
Title: Brightest central galaxies and dry mergers
Speaker: Zugan Deng
Institution: Graduate School of the Chinese Academy of
Sciences, China
Abstract: A sample of local BCGs selected from C4 cluster has been
analysed. Our results show that many BCGs are on going dry mergers.
Our evidence shows that the dry merger rate for BCGs is much higher
than field elliptical galaxies. Detail research of dry merger may
provide important constraints on galaxy formation, especially the
formation of most massive galaxies.
Title: 21 cm signals from ionized and heated regions around first
stars
Speaker: Li-Zhi Fang
Institution: University of Arizona, USA
Abstract: 21 cm signals from the UV ionizing sources in the
reionization epoch is crucial to understand the physics at the end
of dark ages. The formation and evolution of 21 cm emission and
absorption regions depend essentially on the kinetics of photons in
the physical and frequency spaces. To solve the radiative transfer
equation, we use the WENO algorithm, which is effective to capture
the sharp ionization profile and the cut-off at the front of light
and to handle the small fraction of neutral hydrogen and helium in
the ionized sphere. We show that a spherical shell of 21 cm emission
and absorption will develop around a point source once the speed of
the ionization front (I-front) is significantly lower than the speed
of light. The 21 cm shell extends from the I-front to the front of
light; its inner part is the emission region and its outer part is
the absorption region. The 21 cm emission region depends strongly on
the intensity, frequency-spectrum and life-time of the UV ionizing
source. For a source of short life-time, no 21 cm emission region
can be formed if the source dies out before the I-front speed is
significantly lower than the speed of light. Yet, a 21 cm absorption
region can form and develop even after the emission of the source
ceases.
Title: A New Fast Algorithm of Cosmic Statistics for Large Data
Sets
Speaker: Long-long Feng
Institution: Purple Mountain Observatory, China
Abstract: Based on the Beylkin-Cramer summation rule, we introduce a new fast
algorithm that enable us to explore the high order statistics
efficiently in large data sets. Central to this technique is to make
decomposition both of fields and operators within the framework of
multi-resolution analysis (MRA), and realize theirs discrete
representations. Accordingly, a homogenous point process could be
equivalently described by a operation of a Toeplitz matrix on a
vector, which is accomplished by making use of fast Fourier
transformation. The algorithm could be applied widely in the cosmic
statistics to tackle large data sets. In the numerical
procedures, the algorithm scaled with $O(N\log N)$ is
significantly faster than the current particle-based methods, and
its computational cost does not relies on shape or size of sampling
cells. In addition, based on this technique, we propose further a
simple fast scheme to compute the second statistics for cosmic
density fields and justify it using simulation samples. Hopefully,
the technique developed here allows us to make a comprehensive study
of non-Gaussianity of the cosmic fields in high precision cosmology.
Title: Phenomenological Models of Dark Energy
Speaker: Changjun Gao
Institution: National Astronomical Observatories of China
Abstract: two phenomenological models of dark energy are presented.
They give a possible explanationfor both the fine-tuning and the
coincidence problem. Also they are consistent with the observations
very well. The quintessence theory of the models is also constructed.
Title: The first stars, how much we know (review)
Speaker: Liang Gao
Institution: Durham University, UK
Abstract: Here I shortly review the progresses in understanding the
formation of the first stars.
6. Title: Cold Gas and Star Formation in Early Universe
Speaker: Yu Gao
Institute: Purple Mountain Observatory, China
Abstract: We are soon-to-be available for the study of star
formation in galaxies at high redshift. I will emphasize on the
detection of the cold gas most relevant to the active star formation
in galaxies in the early Universe, the current status of this
research field highlighted by several dozens of CO detections and a
few detections in other molecules such as HCN, and future directions
in the next few years.
Title: Cold Gas and Star Formation in Early Universe
Speaker: Yu Gao
Institution: Purple Mountain Observatory, China
Abstract: I will try to introduce some major facilities currently
available and some soon-to-be available (e.g., two major telescopes
ALMA and EVLA) for the study of star formation in galaxies at high
redshift. I will emphasize on the detection of the cold gas most
relevant to the active star formation in galaxies at high redshift,
the current status of this research field highlighted by several
dozens of CO detections and a few detections in other molecules
such as HCN, and future directions in the next few years.
Title: From galaxy distribution to AGN
Speaker: Yipeng Jing
Institution: Shanghai Astronomical Observatory, China
Abstract: I will talk about recent results from redshift surveys about the galaxy distribution and the environment of AGN, and their implication for thoeretical modeling of galaxy formation.
Title: Primordial magnetic fields from dark energy
Speaker: Wolung Lee
Institution: Taiwan Normal University, Taiwan
Abstract: Evidences indicate that the dark energy constitutes about
two thirds of the critical density of the universe. If the dark
energy is an evolving pseudo scalar field that couples to
electromagnetism, a cosmic magnetic seed field can be produced via
spinoidal instability during the formation of large-scale
structures.
Title: Strong lensing by clusters of galaxies and searching for
high-z object
Speaker: Shude Mao
Institution: University of Manchester, UK
Abstract: I will discuss some recent work on strong lensing by
clusters of galaxies, and their cosmological implications. I will
give a brief review of searches for high-z objects (by others)
using strongly lensed clusters.
Title: Fractional Brownian Motion and halo model
Speaker: Jun Pan
Institution: Purple Mountain Observatory, China
Abstract: Fractional Brownian motion (FBM) is a concept which
extends the normal Brownian motion by introducing correlation
between steps of corresponding random walks. The idea is to
generalise the excursion set theory for halo models with the FBM.
The mass function, merger rate, merging history and halo biases are
all revisited with the new formalism. Comparison with simulations
indicates that the application of FBM is very sucessful and thus we
can reliably renovate the halo model to perform analytical
theoretical calculation with the spherical collapse.
Title: Extra dimensions: implications for dark matter detection
Speaker: Bo Qin
Institute: National Astronomical Observatories of China
Abstract: If our space has hidden dimensions, gravity would deviate
from Newtonian gravity and be greatly enhanced on small distance
scales. We show that if these extra dimensions are large and flat,
as in the ADD scenario, then the cross section between dark matter
and ordinary matter would be increased by many orders of magnitude
due to this new gravity. We discuss on possible implications for
dark matter detection experiments.
Title: 21 Centimeter Array (21CMA): Probe of the Reionization
Epoch
Speaker: Xiang-Ping Wu
Institution: National Astronomical
Observatories of China
Abstract: 21CMA is an interferometric radio array dedicated to
measurement of the redshifted 21 cm emission signatures of neutral
hydrogen against CMB in the epoch of reionization. The array,
located in Xinjiang, west China, consists of 81 pods with a total of
10287 log periodic antennas. It operates at frequencies from 50 to
200 MHz, covering a reshishift range of 6-27. In this talk, I will
present the motivation, construction, performance and progress of
21CMA and its impact on our understanding of the history of
reionization.
Title: Dimensionality in Quantum Cosmology
Speaker: Zhong Chao Wu
Institution: Zhejiang University of Technology
Abstract: TBA
Title: Mid-infrared properties of IR QSOs
Speaker: Xiaoyang Xia
Institution: Tianjin Normal University, China
Abstract: We perform the statistical analysis for the mid-infrared
properties of IR QSOs based on Spitzer IRS data. By comparing with
PG QSOs and ULIRGs, it is clear that the IR QSOs are in the
transition stage from massive starburst to classical QSOs. The close
anti-correlation between 6.2mum PAH emission and the blueshift of
Balmer lines is likely the evidence for the AGN feedback that heats
and blows away surrounding cold gas and finally ceases star
formation.
Title: Passively Evolving Galaxy Population as Seen by the GOODS
Spitzer Observations
Speaker: Haojing Yan
Institution: Carnegie Observatories, USA
Abstract: Using the deep Infrared Array Camera (IRAC) observations
of the Great Observatories Origins Deep Survey (GOODS) Spitzer
Legacy Program, we construct a large sample of IRAC-selected
Extremely Red Objects (IEROs; Yan et al. 2004). Such IEROs are
luminous in IRAC passbands, but are very faint or even invisible in
optical. Our previous work in the HUDF shows that such a population
is likely dominated by very massive, passively-evolving, very old
galaxies at z~2.4. This current study will extend to a much wider
field, and will investigate 1) the fraction of passively-evolving
galaxies; 2) the overlapping fraction between IEROs and other types
of red galaxies such as EROs and DRGs; 3) the contribution of IEROs
to the global stellar mass density; and 4) their progenitors and
descendants.
Title: Cosmology with the Large Synoptic Survey Telescope
(review on probes of dark energy)
Speaker: Hu Zhan
Institution: University of California, Davis, USA
Abstract: The proposed Large Synoptic Survey Telescope (LSST)
will carry out a deep half-sky 6-band imaging survey, obtaining
more than 3 billion galaxies and millions of supernovae. I will
discuss the LSST science opportunities with a focus on the
techniques of probing dark energy and dark matter, which include
weak lensing, baryon acoustic oscillations, type Ia supernovae,
and cluster counting. I will present innovative ways of using
the survey data that enable better control on systematics and
tighten the cosmological constraints. Finally, I will give a brief
assessment on observing high-z galaxies and GRBs with LSST.
Title: Wavelet and Weak Lensing
Speaker: Tong-Jie Zhang
Institution: Beijing Normal University, China
Abstract: Weak lesning of galaxies by large scale structure is a poweful tool to mesure the
matter density parameter \Omega_m of the universe. In this talk I will talk about
the weak lensing of CMB polarization by large scal structure. Wavelet analyse is
applied in the smoothing of the lensed convergence, T, E and B mode for CMB.
Futher, we get the constraint on the \Omega_m and the equation of state(EoS) w for
dark energy.
Title: Dense and Warm Molecular Gas in Prorotypical Ulirg Arp 220
Speaker: Jun-Hui Zhao
Authors: Jun-Hui Zhao and Tao An
Abstract: Arp 220 is the prototypical utltra-luminous infrared galaxy
(ULIRG) with Lir = 1.4 x 10^12 solar luminosities.
Two compact components in the nuclear region have been
observed at radio and IR wavelengths. This galaxy is thought to
be in the final stages of galaxy-galaxy merging. Study of Arp 220
could provide us detailed information on the astrophysical
processes in the galaxies at high red-shifts. We present the
results from SMA observations of Arp 220 in multiple CO transitions
of J=6-5, 3-2, 2-1 and the isotope 13CO at J=2-1 at 690, 340 and 230
GHz with the Submillimeter Array (SMA) in angular resolutions of
sub-arcsec to a few arcsec. Based on the measured ratios, we
modeled the excitation condition of the molecular clouds, suggesting
that the CO J=6-5 emission arises from dense (n[H2]~10^5 cm^-3) and warm
(Tk ~ 100 K) cloud components. Each of CO J=6-5 clumps contains
at least a few times 10^8 solar-mass molecular gas, suggesting
presence of a few super giant molecular clouds (GMCs) in Arp 220.
The dense, warm molecular clouds are likely to be the consequence
of the galaxy merger. Properties determined from the super GMCs
suggest that they are in different stages of star formation.
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