26,646 research outputs found
A Unified Approach towards Describing Rapidity and Transverse Momentum Distributions in Thermal Freeze-Out Model
We have attempted to describe the rapidity and transverse momentum spectra,
simultaneously, of the hadrons produced in the Ultra-relativistic Nuclear
Collisions. This we have tried to achieve in a single statistical thermal
freeze-out model using single set of parameters. We assume the formation of a
hadronic gas in thermo-chemical equilibrium at the freeze-out. The model
incorporates a longitudinal as well as a transverse hydrodynamic flow. We have
also found that the role of heavier hadronic resonance decay is important in
explaining the particle spectra.Comment: 22 pages, 11 figure
Lifetime Constraints for Late Dark Matter Decay
We consider a class of late-decaying dark-matter models, in which a dark
matter particle decays to a heavy stable daughter of approximately the same
mass, together with one or more relativistic particles which carry away only a
small fraction of the parent rest mass. Such decays can affect galactic halo
structure and evolution, and have been invoked as a remedy to some of the small
scale structure-formation problems of cold dark matter. There are existing
stringent limits on the dark matter lifetime if the decays produce photons. By
considering examples in which the relativistic decay products instead consist
of neutrinos or electron-position pairs, we derive stringent limits on these
scenarios for a wide range of dark matter masses. We thus eliminate a sizable
portion of the parameter space for these late decay models if the dominant
decay channel involves Standard Model final states.Comment: 13 pages, 7 figures. Replaced to match published version. Discussion
expanded. References added. Accepted by Phys. Rev
Searching for Dark Matter at the LHC with a Mono-Z
We investigate a mono-Z process as a potential dark matter search strategy at
the LHC. In this channel a single Z boson recoils against missing transverse
momentum, attributed to dark matter particles, , which escape the
detector. This search strategy is related, and complementary to, monojet and
monophoton searches. For illustrative purposes we consider the process
in a toy dark matter model, where the Z boson is
emitted from either the initial state quarks, or from the internal propagator.
Among the signatures of this process will be a pair of muons with high pT that
reconstruct to the invariant mass of the Z, and large amounts of missing
transverse energy. Being a purely electroweak signal, QCD and other Standard
Model backgrounds are relatively easily removed with modest selection cuts. We
compare the signal to Standard Model backgrounds and demonstrate that, even for
conservative cuts, there exist regions of parameter space where the signal may
be clearly visible above background in future LHC data, allowing either new
discovery potential or the possibility of supplementing information about the
dark sector beyond that available from other observable channels.Comment: 11 pages, 13 figure
Dilemma and Quantum Battle of Sexes
We analysed quantum version of the game battle of sexes using a general
initial quantum state. For a particular choice of initial entangled quantum
state it is shown that the classical dilemma of the battle of sexes can be
resolved and a unique solution of the game can be obtained.Comment: Revised, Latex, 9 pages, no figure, corresponding author's email:
[email protected]
The impact of utilising mobile assisted language learning (MALL) on vocabulary acquisition among migrant women English learners
Aim/Purpose
To develop a framework for utilizing Mobile Assisted Language Learning (MALL) to assist non-native English migrant women to acquire English vocabulary in a non-formal learning setting.
Background
The women in this study migrated to Australia with varied backgrounds including voluntary or forced migration, very low to high levels of their first language (L1), low proficiency in English, and isolated fulltime stay-at-home mothers.
Methodology
A case study method using semi-structured interviews and observations was used. Six migrant women learners attended a minimum of five non-MALL sessions and three participants continued on and attended a minimum of five MALL sessions. Participants were interviewed pre- and post-sessions. Data were analysed thematically.
Contribution
The MALL framework is capable of enriching migrant women’s learning experience and vocabulary acquisition.
Findings
Vocabulary acquisition occurred in women from both non-MALL and MALL environment; however, the MALL environment provided significantly enriched vocabulary learning experience.
Future Research
A standardised approach to measure the effectiveness of MALL for vocabulary acquisition among migrant women in non-formal settin
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