400 research outputs found
Analisis Pengaruh Faktor-faktor Perilaku Konsumen Terhadap Keputusan Pembelian Makanan Mie Instanmerek Indomie
Tujuan penelitian ini adalah 1. Apakah faktor budaya berpengaruh terhadap keputuasan pembelian makanan mie instan merk indomie, 2. Apakah faktor sosial berpengaruh terhadap keputusan pembelian makanan mie instan merk indomie. 3. Apakah faktor pribadi berpengaruh terhadap keputusan pembelian makanan mie instan merk indomie, 4. Apakah faktor psikologis berpengaruh terhadap keputusan pembelian makanan mie istan merk indomie 5. Apakah faktor budaya, sosial pribadi, dan psikologis berpangaruh terhadap keputusan pembelian makanan mie instan merk indomie. Populasi penelitian ini adalah mahasiswa Fakultas Ekonomi dan Bisnis, Fakultas ilmu Sosial dan Politik dan Fakultas Pertanian, teknik pengumpulan data adalah mengunakan non probability sampling dengan jumlah sampel sebanyak 100 orang. Instrument penelitian mengunakan kuesioner yang telah memenuhi syarat validitas dan relaibilitas sedangkan analisis data mengunakan analisis regresi linear berganda. Secara parsial diketahui bahwa nilai signifikan: faktor budaya sebesar 0,197, faktor sosial sebesar -0,014, faktor pribadi sebesar 0,327, faktor psikologis sebesar 0,386, sedangkan secara simultan nilai signifikan sebesar 0,000. Untuk faktor Sosial ditemukan tidak signifikan terhadap keputusan pembelian makanan mie instan merek Indomie. Secara simultan faktor budaya, sosial, pribadi, dan psikologis berpengaruh terhadap keputusan pembelian makanan mie instan merek Indomie
First Direct Detection Limits on sub-GeV Dark Matter from XENON10
The first direct detection limits on dark matter in the MeV to GeV mass range
are presented, using XENON10 data. Such light dark matter can scatter with
electrons, causing ionization of atoms in a detector target material and
leading to single- or few-electron events. We use 15 kg-days of data acquired
in 2006 to set limits on the dark-matter-electron scattering cross section. The
strongest bound is obtained at 100 MeV where sigma_e < 3 x 10^{-38} cm^2 at 90%
CL, while dark matter masses between 20 MeV and 1 GeV are bounded by sigma_e <
10^{-37} cm^2 at 90% CL. This analysis provides a first proof-of-principle that
direct detection experiments can be sensitive to dark matter candidates with
masses well below the GeV scale.Comment: Submitted to PR
A Definitive Signal of Multiple Supersymmetry Breaking
If the lightest observable-sector supersymmetric particle (LOSP) is charged
and long-lived, then it may be possible to indirectly measure the Planck mass
at the LHC and provide a spectacular confirmation of supergravity as a symmetry
of nature. Unfortunately, this proposal is only feasible if the gravitino is
heavy enough to be measured at colliders, and this condition is in direct
conflict with constraints from big bang nucleosynthesis (BBN). In this work, we
show that the BBN bound can be naturally evaded in the presence of multiple
sectors which independently break supersymmetry, since there is a new decay
channel of the LOSP to a goldstino. Certain regions of parameter space allow
for a direct measurement of LOSP decays into both the goldstino and the
gravitino at the LHC. If the goldstino/gravitino mass ratio is measured to be
2, as suggested by theory, then this would provide dramatic verification of the
existence of multiple supersymmetry breaking and sequestering. A variety of
consistent cosmological scenarios are obtained within this framework. In
particular, if an R symmetry is imposed, then the gauge-gaugino-goldstino
interaction vertices can be forbidden. In this case, there is no bound on the
reheating temperature from goldstino overproduction, and thermal leptogenesis
can be accommodated consistently with gravitino dark matter.Comment: 10 pages, 5 figures, title changed to match the version published in
JHE
A Brief Review on Dark Matter Annihilation Explanation for Excesses in Cosmic Ray
Recently data from PAMELA, ATIC, FERMI-LAT and HESS show that there are
excesses in the cosmic ray energy spectrum. PAMELA observed excesses
only in , but not in anti-proton spectrum. ATIC, FERMI-LAT and HESS
observed excesses in spectrum, but the detailed shapes are different
which requires future experimental observations to pin down the correct data
set. Nevertheless a lot of efforts have been made to explain the observed
excesses, and also why PAMELA only observed excesses in but not
in anti-proton. In this brief review we discuss one of the most popular
mechanisms to explain the data, the dark matter annihilation. It has long been
known that about 23% of our universe is made of relic dark matter. If the relic
dark matter was thermally produced, the annihilation rate is constrained
resulting in the need of a large boost factor to explain the data. We will
discuss in detail how a large boost factor can be obtained by the Sommerfeld
and Briet-Wigner enhancement mechanisms. Some implications for particle physics
model buildings will also be discussed.Comment: 22 pages, 6 figures. Several typoes corrected and some references
added. Published in Mod. Phys. Lett. A, Vol. 24, No. 27 (2009) pp. 2139-216
Decaying into the Hidden Sector
The existence of light hidden sectors is an exciting possibility that may be
tested in the near future. If DM is allowed to decay into such a hidden sector
through GUT suppressed operators, it can accommodate the recent cosmic ray
observations without over-producing antiprotons or interfering with the
attractive features of the thermal WIMP. Models of this kind are simple to
construct, generic and evade all astrophysical bounds. We provide tools for
constructing such models and present several distinct examples. The light
hidden spectrum and DM couplings can be probed in the near future, by measuring
astrophysical photon and neutrino fluxes. These indirect signatures are
complimentary to the direct production signals, such as lepton jets, predicted
by these models.Comment: 40 pages, 5 figure
Singlet Portal to the Hidden Sector
Ultraviolet physics typically induces a kinetic mixing between gauge singlets
which is marginal and hence non-decoupling in the infrared. In singlet
extensions of the minimal supersymmetric standard model, e.g. the
next-to-minimal supersymmetric standard model, this furnishes a well motivated
and distinctive portal connecting the visible sector to any hidden sector which
contains a singlet chiral superfield. In the presence of singlet kinetic
mixing, the hidden sector automatically acquires a light mass scale in the
range 0.1 - 100 GeV induced by electroweak symmetry breaking. In theories with
R-parity conservation, superparticles produced at the LHC invariably cascade
decay into hidden sector particles. Since the hidden sector singlet couples to
the visible sector via the Higgs sector, these cascades necessarily produce a
Higgs boson in an order 0.01 - 1 fraction of events. Furthermore,
supersymmetric cascades typically produce highly boosted, low-mass hidden
sector singlets decaying visibly, albeit with displacement, into the heaviest
standard model particles which are kinematically accessible. We study
experimental constraints on this broad class of theories, as well as the role
of singlet kinetic mixing in direct detection of hidden sector dark matter. We
also present related theories in which a hidden sector singlet interacts with
the visible sector through kinetic mixing with right-handed neutrinos.Comment: 12 pages, 5 figure
Neutralino Dark Matter in BMSSM Effective Theory
We study thermal neutralino dark matter in an effective field theory
extension of the MSSM, called "Beyond the MSSM" (BMSSM) in Dine, Seiberg and
Thomas (2007). In this class of effective field theories, the field content of
the MSSM is unchanged, but the little hierarchy problem is alleviated by
allowing small corrections to the Higgs/higgsino part of the Lagrangian. We
perform parameter scans and compute the dark matter relic density. The light
Higgsino LSP scenario is modified the most; we find new regions of parameter
space compared to the standard MSSM. This involves interesting interplay
between the WMAP dark matter bounds and the LEP chargino bound. We also find
some changes for gaugino LSPs, partly due to annihilation through a Higgs
resonance, and partly due to coannihilation with light stops in models that are
ruled in by the new effective terms.Comment: 37 pages + appendi
Conservative Constraints on Dark Matter from the Fermi-LAT Isotropic Diffuse Gamma-Ray Background Spectrum
We examine the constraints on final state radiation from Weakly Interacting
Massive Particle (WIMP) dark matter candidates annihilating into various
standard model final states, as imposed by the measurement of the isotropic
diffuse gamma-ray background by the Large Area Telescope aboard the Fermi
Gamma-Ray Space Telescope. The expected isotropic diffuse signal from dark
matter annihilation has contributions from the local Milky Way (MW) as well as
from extragalactic dark matter. The signal from the MW is very insensitive to
the adopted dark matter profile of the halos, and dominates the signal from
extragalactic halos, which is sensitive to the low mass cut-off of the halo
mass function. We adopt a conservative model for both the low halo mass
survival cut-off and the substructure boost factor of the Galactic and
extragalactic components, and only consider the primary final state radiation.
This provides robust constraints which reach the thermal production
cross-section for low mass WIMPs annihilating into hadronic modes. We also
reanalyze limits from HESS observations of the Galactic Ridge region using a
conservative model for the dark matter halo profile. When combined with the
HESS constraint, the isotropic diffuse spectrum rules out all interpretations
of the PAMELA positron excess based on dark matter annihilation into two lepton
final states. Annihilation into four leptons through new intermediate states,
although constrained by the data, is not excluded.Comment: 11 pages, 5 figures. v3: minor revisions, matches version to appear
in JCA
Decaying Hidden Dark Matter in Warped Compactification
The recent PAMELA and ATIC/Fermi/HESS experiments have observed an excess of
electrons and positrons, but not anti-protons, in the high energy cosmic rays.
To explain this result, we construct a decaying hidden dark matter model in
string theory compactification that incorporates the following two ingredients,
the hidden dark matter scenario in warped compactification and the
phenomenological proposal of hidden light particles that decay to the Standard
Model. In this model, on higher dimensional warped branes, various warped
Kaluza-Klein particles and the zero-mode of gauge field play roles of the
hidden dark matter or mediators to the Standard Model.Comment: 15 pages; v4, several clarifications added, update on Fermi/HESS
result
PAMELA, DAMA, INTEGRAL and Signatures of Metastable Excited WIMPs
Models of dark matter with ~ GeV scale force mediators provide attractive
explanations of many high energy anomalies, including PAMELA, ATIC, and the
WMAP haze. At the same time, by exploiting the ~ MeV scale excited states that
are automatically present in such theories, these models naturally explain the
DAMA/LIBRA and INTEGRAL signals through the inelastic dark matter (iDM) and
exciting dark matter (XDM) scenarios, respectively. Interestingly, with only
weak kinetic mixing to hypercharge to mediate decays, the lifetime of excited
states with delta < 2 m_e is longer than the age of the universe. The
fractional relic abundance of these excited states depends on the temperature
of kinetic decoupling, but can be appreciable. There could easily be other
mechanisms for rapid decay, but the consequences of such long-lived states are
intriguing. We find that CDMS constrains the fractional relic population of
~100 keV states to be <~ 10^-2, for a 1 TeV WIMP with sigma_n = 10^-40 cm^2.
Upcoming searches at CDMS, as well as xenon, silicon, and argon targets, can
push this limit significantly lower. We also consider the possibility that the
DAMA excitation occurs from a metastable state into the XDM state, which decays
via e+e- emission, which allows lighter states to explain the INTEGRAL signal
due to the small kinetic energies required. Such models yield dramatic signals
from down-scattering, with spectra peaking at high energies, sometimes as high
as ~1 MeV, well outside the usual search windows. Such signals would be visible
at future Ar and Si experiments, and may be visible at Ge and Xe experiments.
We also consider other XDM models involving ~ 500 keV metastable states, and
find they can allow lighter WIMPs to explain INTEGRAL as well.Comment: 22 pages, 7 figure
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