Effective inertial frame in an atom interferometric test of the equivalence principle

In an ideal test of the equivalence principle, the test masses fall in a common inertial frame. A real experiment is affected by gravity gradients, which introduce systematic errors by coupling to initial kinematic differences between the test masses. We demonstrate a method that reduces the sensitivity of a dual-species atom interferometer to initial kinematics by using a frequency shift of the mirror pulse to create an effective inertial frame for both atomic species. This suppresses the gravity-gradient-induced dependence of the differential phase on initial kinematic differences by a factor of 100 and enables a precise measurement of these differences. We realize a relative precision of $\Delta g / g \approx 6 \times 10^{-11}$ per shot, which improves on the best previous result for a dual-species atom interferometer by more than three orders of magnitude. By suppressing gravity gradient systematic errors to below one part in $10^{13}$, these results pave the way for an atomic test of the equivalence principle at an accuracy comparable with state-of-the-art classical tests.Comment: 5 pages, 4 figure

OVI, NV and CIV in the Galactic Halo: II. Velocity-Resolved Observations with Hubble and FUSE

We present a survey of NV and OVI (and where available CIV) in the Galactic halo, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope (HST) along 34 sightlines. These ions are usually produced in nonequilibrium processes such as shocks, evaporative interfaces, or rapidly cooling gas, and thus trace the dynamics of the interstellar medium. Searching for global trends in integrated and velocity-resolved column density ratios, we find large variations in most measures, with some evidence for a systematic trend of higher ionization (lower NV/OVI column density ratio) at larger positive line-of-sight velocities. The slopes of log[N(NV)/N(OVI)] per unit velocity range from -0.015 to +0.005, with a mean of -0.0032+/-0.0022(r)+/-0.0014(sys) dex/(km/s). We compare this dataset with models of velocity-resolved high-ion signatures of several common physical structures. The dispersion of the ratios, OVI/NV/CIV, supports the growing belief that no single model can account for hot halo gas, and in fact some models predict much stronger trends than are observed. It is important to understand the signatures of different physical structures to interpret specific lines of sight and future global surveys.Comment: ApJ in press 43 pages, 22 fig

Aktivitas Sitotoksik Dari Ekstrak Bintang Ular (Ophiomastix Annulosa) Terhadap Perkembangan Awal Embrio Bulu Babi (Tripneustes Gratilla)

Penelitian di bidang alam bahari telah berkembang ditandai dengan ditemukannya substansi-substansi seperti sitotoksik, antimikroba, antifungi dan sebagainya yang dibutuhkan dalam penyediaan bahan-bahan farmasi. Penelitian ini bertujuan untuk mendeteksi ada tidaknya substansi sititoksik pada bintang ular Ophimastix annulosa dan menelusuri keberadaan senyawanya. Sampel diekstraksi dengan pelarut metanol, kemudian dipartisi menggunakan pelarut etil asetat, heksan dan kloroform. Tiap fraksi diuji pada sel telur bulu babi (Tripneustes gratilla) sebelum dan sesudah difertilisasi. Hasil pengamatan menunjukkan bahwa ekstrak metanolik O. annulosa dan ketiga fraksi (etil asetat, heksan dan kloroform) memiliki substans sitotoksik. keempat fraksi yang diuji mampu menghambat perkembangan sel telur dan embrio bulu babi. fraksi kloroform menunjukkan aktivitas sitotoksik tertinggi dibandingkan ketiga fraksi lainnya sehingga perlu dilakukan pemurnian lanjut untuk menemukan senyawa murni

Three photometric methods tested on ground-based data of Q 2237+0305

The Einstein Cross, Q~2237+0305, has been photometrically observed in four bands on two successive nights at NOT (La Palma, Spain) in October 1995. Three independent algorithms have been used to analyse the data: an automatic image decomposition technique, a CLEAN algorithm and the new MCS deconvolution code. The photometric and astrometric results obtained with the three methods are presented. No photometric variations were found in the four quasar images. Comparison of the photometry from the three techniques shows that both systematic and random errors affect each method. When the seeing is worse than 1.0", the errors from the automatic image decomposition technique and the Clean algorithm tend to be large (0.04-0.1 magnitudes) while the deconvolution code still gives accurate results (1{sigma} error below 0.04) even for frames with seeing as bad as 1.7". Reddening is observed in the quasar images and is found to be compatible with either extinction from the lensing galaxy or colour dependent microlensing. The photometric accuracy depends on the light distribution used to model the lensing galaxy. In particular, using a numerical galaxy model, as done with the MCS algorithm, makes the method less seeing dependent. Another advantage of using a numerical model is that eventual non-homogeneous structures in the galaxy can be modeled. Finally, we propose an observational strategy for a future photometric monitoring of the Einstein Cross.Comment: 9 pages, accepted for publication in A&

Variable Selection and Model Averaging in Semiparametric Overdispersed Generalized Linear Models

We express the mean and variance terms in a double exponential regression model as additive functions of the predictors and use Bayesian variable selection to determine which predictors enter the model, and whether they enter linearly or flexibly. When the variance term is null we obtain a generalized additive model, which becomes a generalized linear model if the predictors enter the mean linearly. The model is estimated using Markov chain Monte Carlo simulation and the methodology is illustrated using real and simulated data sets.Comment: 8 graphs 35 page

Uji Aktivitas Larvasida Nyamuk Aedes Aegypti Dari Beberapa Ekstrak Ascidian

Dengue Hemorrhagic Fever (DHF) is a disease caused by virus through Aedesaegypti mosquitoes as the vector. The disease is spreading across the world andendanger and threaten human life. Measures in controlling the vector using the commonlarvaside “abate” are in adequate and less affective. The objectives of the research is tofind out larvaside extracted from three kinds of ascidian. The each ascidians (Polycarpaaurata, Didemnum molle and Rophalaea crassa) were extracted with ethanol, and thecrude extracts were subjected to larvasidal test by dissolving in water containing thelarvae. The remarkable extract activity was partition in ethyl acetate, hexane andbuthanol. The results show that extract of Polycarpa aurata has the highest activity. Theactivity of fractions show that ethyl acetate at 100 ppm reveals the highest mortality oflarvae 100% in 8 hours, followed by hexane fraction (12 hours) then buthanol fraction (18hours). All the fractions (Ethyl acetate, Hexane and Buthanol) could totality kill the larvaewithin 24 hours which is comparable to the abate

A photonic crystal Josephson traveling wave parametric amplifier

An amplifier combining noise performances as close as possible to the quantum limit with large bandwidth and high saturation power is highly desirable for many solid state quantum technologies such as high fidelity qubit readout or high sensitivity electron spin resonance for example. Here we introduce a new Traveling Wave Parametric Amplifier based on Superconducting QUantum Interference Devices. It displays a 3 GHz bandwidth, a -102 dBm 1-dB compression point and added noise near the quantum limit. Compared to previous state-of-the-art, it is an order of magnitude more compact, its characteristic impedance is in-situ tunable and its fabrication process requires only two lithography steps. The key is the engineering of a gap in the dispersion relation of the transmission line. This is obtained using a periodic modulation of the SQUID size, similarly to what is done with photonic crystals. Moreover, we provide a new theoretical treatment to describe the non-trivial interplay between non-linearity and such periodicity. Our approach provides a path to co-integration with other quantum devices such as qubits given the low footprint and easy fabrication of our amplifier.Comment: 6 pages, 4 figures, Appendixe

Detection of x-rays from galaxy groups associated with the gravitationally lensed systems PG 1115+080 and B1422+231

Gravitational lenses that produce multiple images of background quasars can be an invaluable cosmological tool. Deriving cosmological parameters, however, requires modeling the potential of the lens itself. It has been estimated that up to a quarter of lensing galaxies are associated with a group or cluster which perturbs the gravitational potential. Detection of X-ray emission from the group or cluster can be used to better model the lens. We report on the first detection in X-rays of the group associated with the lensing system PG 1115+080 and the first X-ray image of the group associated with the system B1422+231. We find a temperature and rest-frame luminosity of 0.8 +/- 0.1 keV and 7 +/- 2 x 10^{42} ergs/s for PG 1115+080 and 1.0 +infty/-0.3 keV and 8 +/- 3 x 10^{42} ergs/s for B1422+231. We compare the spatial and spectral characteristics of the X-ray emission to the properties of the group galaxies, to lens models, and to the general properties of groups at lower redshift.Comment: Accepted for publication in ApJ. 17 pages, 5 figures. Minor changes to tex

Étude cinématique des événements binaires et ternaires obtenus par bombardement de cibles d'U, Th, Bi, Pb, Au par des deutons de 2,1 GeV

Une étude cinématique de la fission binaire et ternaire induite par des deutons de 2,1 GeV sur des cibles U, Th, Pb, Bi et Au est réalisée à partir des caractéristiques géométriques des traces des fragments des événements enregistrés dans un détecteur solide de traces en géométrie 4π. Moyennant certaines hypothèses, on établit la distribution en rapport de masse et en énergie des fragments. On a pu mettre en évidence qu'une partie des événements binaires dont l'angle projeté sur le plan perpendiculaire à la trajectoire de la particule incidente est différent de 180°, procèdent d'un même type de désintégration que les événements ternaires. De même, l'analyse cinématique des événements ternaires montre une certaine analogie avec le phénomène connu de la tripartition de noyaux lourds comme le californium par exemple, et pourrait expliquer la production d'une partie des isotopes légers et lourds déficients en neutrons attribués à de la fragmentation par les radio-chimistes