2,354 research outputs found

    Water cooling of shocks in protostellar outflows: Herschel-PACS map of L1157

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    Context. The far-IR/sub-mm spectral mapping facility provided by the Herschel-PACS and HIFI instruments has made it possible to obtain, for the first time, images of H_2O emission with a spatial resolution comparable to ground based mm/sub-mm observations. Aims. In the framework of the Water In Star-forming regions with Herschel (WISH) key program, maps in water lines of several outflows from young stars are being obtained, to study the water production in shocks and its role in the outflow cooling. This paper reports the first results of this program, presenting a PACS map of the o-H_2O 179 μm transition obtained toward the young outflow L1157. Methods. The 179 μm map is compared with those of other important shock tracers, and with previous single-pointing ISO, SWAS, and Odin water observations of the same source that allow us to constrain the H_2O abundance and total cooling. Results. Strong H_2O peaks are localized on both shocked emission knots and the central source position. The H_2O 179 μm emission is spatially correlated with emission from H_2 rotational lines, excited in shocks leading to a significant enhancement of the water abundance. Water emission peaks along the outflow also correlate with peaks of other shock-produced molecular species, such as SiO and NH_3. A strong H_2O peak is also observed at the location of the proto-star, where none of the other molecules have significant emission. The absolute 179 μm intensity and its intensity ratio to the H_2O 557 GHz line previously observed with Odin/SWAS indicate that the water emission originates in warm compact clumps, spatially unresolved by PACS, having a H_2O  abundance of the order of 10^(-4). This testifies that the clumps have been heated for a time long enough to allow the conversion of almost all the available gas-phase oxygen into water. The total H_2O cooling is ~10^(-1) L_☉, about 40% of the cooling due to H_2 and 23% of the total energy released in shocks along the L1157 outflow

    CH2D+, the Search for the Holy Grail

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    CH2D+, the singly deuterated counterpart of CH3+, offers an alternative way to mediate formation of deuterated species at temperatures of several tens of K, as compared to the release of deuterated species from grains. We report a longstanding observational search for this molecular ion, whose rotational spectroscopy is not yet completely secure. We summarize the main spectroscopic properties of this molecule and discuss the chemical network leading to the formation of CH2D+, with explicit account of the ortho/para forms of H2, H3+ and CH3+. Astrochemical models support the presence of this molecular ion in moderately warm environments at a marginal level.Comment: 25 pages, 6 Figures Accepted in Journal of Physical Chemistry A. "Oka Festschrift: Celebrating 45 years of Astrochemistry

    Pengaruh Rasio Capital Adequacy, Loan to Deposit, Net Interest Margin Terhadap Pertumbuhanlaba (Studi Kasus Pada Bank Umum Konvensionalyang Terdaftar Di Bursa Efek Indonesia)

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    This study is how Influence Ratio Capital Adequacy Ratio, Loan to Deposit Ratio, Net Interest Margin Against Profit Growth at Conventional Commercial Banks Listed on Indonesia Stock Exchange. the purpose of this study is to analyze the Influence of Capital Adequacy Ratio Ratio, Loan to Deposit Ratio, Net Interest Margin on Profit Growth at Conventional Commercial Banks Listed on Indonesia Stock Exchange. The type of research used is associative research. The research population is conventional commercial bank in Indonesia. The research variables are Capital Adequacy Ratio (CAR), Loan to Deposit Ratio (LDR), Net Interest Margin (NIM), and Profit Growth. The data used is secondary data. Data collection methods are quantitative. Partial test results show that NIM has a significant effect on Profit Growth, While CAR and LDR have no significant effect to Profit Growth

    Evaluation of the usefulness of carcass-weight, meat-percentage or identity of pig-producer in future-risk-based meat inspection

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    In the search for new and risk-based ways of conducting meat inspection, a pilot study was conducted with the amin of investigating whether carcass weight in combination with meat percentage, or producer-identity could be used as indicators for rejection of finisher pig carcasses

    The CHESS spectral survey of star forming regions: Peering into the protostellar shock L1157-B1 - II. Shock dynamics

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    Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent. Aims. We present the first results of the unbiased spectral survey of the L1157-B1 bowshock, obtained in the framework of the key program “Chemical HErschel Surveys of star forming regions” (CHESS). The main aim is to trace the warm and chemically enriched gas and to infer the excitation conditions in the shock region. Methods. The CO 5-4 and o-H2_O 1_(10)–1_(01) lines have been detected at high-spectral resolution in the unbiased spectral survey of the HIFI-band 1b spectral window (555–636 GHz), presented by Codella et al. in this volume. Complementary ground-based observations in the submm window help establish the origin of the emission detected in the main-beam of HIFI and the physical conditions in the shock. Results. Both lines exhibit broad wings, which extend to velocities much higher than reported up to now. We find that the molecular emission arises from two regions with distinct physical conditions : an extended, warm (100 K), dense (3 × 10^5 cm^(-3)) component at low-velocity, which dominates the water line flux in Band 1; a secondary component in a small region of B1 (a few arcsec) associated with high-velocity, hot (>400 K) gas of moderate density ((1.0–3.0) × 10^4 cm^(-3)), which appears to dominate the flux of the water line at 179μm observed with PACS. The water abundance is enhanced by two orders of magnitude between the low- and the high-velocity component, from 8 × 10^(-7) up to 8 × 10^(-5). The properties of the high-velocity component agree well with the predictions of steady-state C-shock models

    Kematangan Emosi, Konsep Diri Dan Kenakalan Remaja

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    Emotionol maturity, self-concept, and juvenile delinquency examined on 120 middle adolescents. Researcher developed three research instrament of measurement, namely the scale of juvenile delinquency, the scale of emotional maturity, and the self-concept scale. Data analyzed with the multiple regression. Varians proportion of juvenile delinquency can be explained through the emotional maturity and self-concept. Emotional moturity and self-concept simultaneously predict delinquency in undirectional and linear relationships; Emotional maturity is a psychological capacity that has the potential to allow a decline in juvenile delinquency; Self-concept is a psychological capacity that no potential to allow the reducticn or increase in juvenile delinquency. Juvenile delinquency data not normally distributed and relativety high. Prediction research, findings apply only to groups of adolescents with high delinquency, rates. The findings are discussed in terms of their implications for middle adolescent in context

    Excitation and abundance of C_3 in star forming cores: Herschel/HIFI observations of the sight-lines to W31C and W49N

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    We present spectrally resolved observations of triatomic carbon (C_3) in several ro-vibrational transitions between the vibrational ground state and the low-energy ν_2 bending mode at frequencies between 1654−1897 GHz along the sight-lines to the submillimeter continuum sources W31C and W49N, using Herschel’s HIFI instrument. We detect C_3 in absorption arising from the warm envelope surrounding the hot core, as indicated by the velocity peak position and shape of the line profile. The sensitivity does not allow to detect C_3 absorption due to diffuse foreground clouds. From the column densities of the rotational levels in the vibrational ground state probed by the absorption we derive a rotation temperature (T_(rot)) of ~50−70 K, which is a good measure of the kinetic temperature of the absorbing gas, as radiative transitions within the vibrational ground state are forbidden. It is also in good agreement with the dust temperatures for W31C and W49N. Applying the partition function correction based on the derived T_(rot), we get column densities N(C_3) ~ 7−9 × 10^(14) cm^(−2) and abundance x(C_3) ~ 10^(−8) with respect to H_2. For W31C, using a radiative transfer model including far-infrared pumping by the dust continuum and a temperature gradient within the source along the line of sight we find that a model with x(C_3) = 10^(−8), T_(kin) = 30−50 K, N(C_3) = 1.5 × 10^(15) cm^(−2) fits the observations reasonably well and provides parameters in very good agreement with the simple excitation analysis

    Reply to the comment of Chudnovsky&Garanin on "Spin relaxation in Mn12-acetate"

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    Reply to the comment of E.M. Chudnovsky and D.A. Garanin on Europhys. Lett. 46, 692 (1999).Comment: 2 pages, Latex (europhys.sty
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