460 research outputs found
Installation of New CSD (Carbonated Soft Drink) RGB (Returnable Glass Bottle) Line with Food Safety Comply and Final Validation
The basic of this project was installation of new CSD (carbonated soft drink) RGB (returnable glass bottle) line with comply food safety and final validation of line. New manufacturing line installation deals with installation of all equipment and machine require for smooth running and producing CSD for COCA-COLA company (Coca-Cola, Thums UP, Limca) such as conveyer belt, uncasing machine, light inspection station, bottle washer EBI (electronic bottle inspection ) machine, Paramix, Filler, Sealer, Date coding machine, caser etc. During installation of machine we have fulfill requirement related to machine, work space, hygienic condition so that machine can work smoothly and deliver safe food product The main concern of doing this project was deliver a safe product to the consumer by applying HACCP and ISO22K. I have done hazard analysis and validation of this new installed line and identify CCP and OPRP which need to control by applying control measure
Barium & related stars and their white-dwarf companions II. Main-sequence and subgiant stars
Barium (Ba) dwarfs and CH subgiants are the less-evolved analogues of Ba and
CH giants. They are F- to G-type main-sequence stars polluted with heavy
elements by a binary companion when the latter was on the Asymptotic Giant
Branch (AGB). This companion is now a white dwarf that in most cases cannot be
directly detected. We present a large systematic study of 60 objects classified
as Ba dwarfs or CH subgiants. Combining radial-velocity measurements from
HERMES and SALT high-resolution spectra with radial-velocity data from CORAVEL
and CORALIE, we determine the orbital parameters of 27 systems. We also derive
their masses by comparing their location in the Hertzsprung-Russell diagram
with evolutionary models. We confirm that Ba dwarfs and CH subgiants are not at
different evolutionary stages and have similar metallicities, despite their
different names. Additionally, Ba giants appear significantly more massive than
their main-sequence analogues. This is likely due to observational biases
against the detection of hotter main-sequence post-mass-transfer objects.
Combining our spectroscopic orbits with the Hipparcos astrometric data, we
derive the orbital inclinations and the mass of the WD companion for four
systems. Since this cannot be done for all systems in our sample yet (but
should be with upcoming Gaia data releases), we also analyse the mass-function
distribution of our binaries. We can model this distribution with very narrow
mass distributions for the two components and random orbital orientation on the
sky. Finally, based on BINSTAR evolutionary models, we suggest that the orbital
evolution of low-mass Ba systems can be affected by a second phase of
interaction along the Red Giant Branch of the Ba star, impacting on the
eccentricities and periods of the giants.Comment: Accepted for publication in A&A on the 5th of April, 201
Kepler eclipsing binary stars. VII. the catalogue of eclipsing binaries found in the entire Kepler data set
The primary Kepler Mission provided nearly continuous monitoring of ~200,000 objects with unprecedented photometric precision. We present the final catalog of eclipsing binary systems within the 105 deg2 Kepler field of view. This release incorporates the full extent of the data from the primary mission (Q0-Q17 Data Release). As a result, new systems have been added, additional false positives have been removed, ephemerides and principal parameters have been recomputed, classifications have been revised to rely on analytical models, and eclipse timing variations have been computed for each system. We identify several classes of systems including those that exhibit tertiary eclipse events, systems that show clear evidence of additional bodies, heartbeat systems, systems with changing eclipse depths, and systems exhibiting only one eclipse event over the duration of the mission. We have updated the period and galactic latitude distribution diagrams and included a catalog completeness evaluation. The total number of identified eclipsing and ellipsoidal binary systems in the Kepler field of view has increased to 2878, 1.3% of all observed Kepler targets
RADIAL VELOCITY MONITORING OFKEPLERHEARTBEAT STARS
Heartbeat stars (HB stars) are a class of eccentric binary stars with close periastron passages. The characteristic photometric HB signal evident in their light curves is produced by a combination of tidal distortion, heating, and Doppler boosting near orbital periastron. Many HB stars continue to oscillate after periastron and along the entire orbit, indicative of the tidal excitation of oscillation modes within one or both stars. These systems are among the most eccentric binaries known, and they constitute astrophysical laboratories for the study of tidal effects. We have undertaken a radial velocity (RV) monitoring campaign of Kepler HB stars in order to measure their orbits. We present our first results here, including a sample of 22 Kepler HB systems, where for 19 of them we obtained the
Keplerian orbit and for 3 other systems we did not detect a statistically significant RV variability. Results presented here are based on 218 spectra obtained with the Keck/HIRES spectrograph during the 2015 Kepler observing season, and they have allowed us to obtain the largest sample of HB stars with orbits measured using a single instrument, which roughly doubles the number of HB stars with an RV measured orbit. The 19 systems measured here have orbital periods from 7 to 90 days and eccentricities from 0.2 to 0.9. We show that HB stars draw the upper envelope of the eccentricity–period distribution. Therefore, HB stars likely represent a population of stars currently undergoing high eccentricity migration via tidal orbital circularization, and they will allow for new tests
of high eccentricity migration theories
Kepler Eclipsing Binary Stars. Vii. The Catalog Of Eclipsing Binaries Found In The Entire Kepler Data Set
The Kepler mission has provided unprecedented, nearly continuous photometric data of ~200,000 objects in the ~105 deg2 field of view (FOV) from the beginning of science operations in May of 2009 until the loss of the second reaction wheel in May of 2013. The Kepler Eclipsing Binary Catalog contains information including but not limited to ephemerides, stellar parameters, and analytical approximation fits for every known eclipsing binary system in the Kepler FOV. Using target pixel level data collected from Kepler in conjunction with the Kepler Eclipsing Binary Catalog, we identify false positives among eclipsing binaries, i.e., targets that are not eclipsing binaries themselves, but are instead contaminated by eclipsing binary sources nearby on the sky and show eclipsing binary signatures in their light curves. We present methods for identifying these false positives and for extracting new light curves for the true source of the observed binary signal. For each source, we extract three separate light curves for each quarter of available data by optimizing the signal-to-noise ratio, the relative percent eclipse depth, and the flux eclipse depth. We present 289 new eclipsing binaries in the Kepler FOV that were not targets for observation, and these have been added to the catalog
Climate change and anthropogenic intervention impact on the hydrologic anomalies in a semi-arid area : lower Zab river basin, Iraq
Climate change impact, drought phenomena and anthropogenic stress are of increasing apprehension for water resource managers and strategists, particularly in arid regions. The current study proposes a generic methodology to evaluate the potential impact of such changes at a basin scale. The Lower Zab River Basin located in the north of Iraq has been selected for illustration purposes. The method has been developed through evaluating changes during normal hydrological years to separate the effects of climate change and estimate the hydrologic abnormalities utilising Indicators of Hydrologic Alteration. The meteorological parameters were perturbed by applying adequate delta perturbation climatic scenarios. Thereafter, a calibrated rainfall-runoff model was used for streamflow simulations. Findings proved that climate change has a more extensive impact on the hydrological characteristics of the streamflow than anthropogenic intervention (i.e. the construction of a large dam in the catchment). The isolated baseflow is more sensitive to the precipitation variations than to the variations of the potential evapotranspiration. The current hydrological anomalies are expected to continue. This comprehensive basin study demonstrates how climate change impact, anthropogenic intervention as well as hydro-climatic drought and hydrological anomalies can be evaluated with a new methodology
Binary-object spectral-synthesis in 3D (BOSS-3D) -- Modelling H-alpha emission in the enigmatic multiple system LB-1
Context: To quantitatively decode the information stored within an observed
spectrum, detailed modelling of the physical state and accurate radiative
transfer solution schemes are required. In the analysis of stellar spectra, the
numerical model often needs to account for binary companions and 3D structures
in the stellar envelopes. The enigmatic binary (or multiple) system LB-1
constitutes a perfect example of such a complex multi-D problem. Aims: To
improve our understanding of the LB-1 system, we directly modelled the
phase-dependent H-alpha line profiles of this system. To this end, we developed
a multi-purpose binary-object spectral-synthesis code in 3D (BOSS-3D). Methods:
BOSS-3D calculates synthetic line profiles for a given state of the
circumstellar material. The standard pz-geometry commonly used for single stars
is extended by defining individual coordinate systems for each involved object
and by accounting for the appropriate coordinate transformations. The code is
then applied to the LB-1 system, considering two main hypotheses, a binary
containing a stripped star and Be star, or a B star and a black hole with a
disc. Results: Comparing these two scenarios, neither model can reproduce the
detailed phase-dependent shape of the H-alpha line profiles. A satisfactory
match with the observations, however, is obtained by invoking a disc around the
primary object in addition to the Be-star disc or the black-hole accretion
disc. Conclusions: The developed code can be used to model synthetic line
profiles for a wide variety of binary systems, ranging from transit spectra of
planetary atmospheres, to post-asymptotic giant branch binaries including
circumstellar and circumbinary discs and massive-star binaries with stellar
winds and disc systems. For the LB-1 system, our modelling provides strong
evidence that each object in the system contains a disc-like structure
The colliding-wind binary HD 168112
peer reviewedRadio surveys of early-type stars have revealed a number of non-thermal
emitters. Most of these have been shown to be binaries, where the collision
between the two stellar winds is responsible for the non-thermal emission. HD
168112 is a non-thermal radio emitter, whose binary nature has only recently
been confirmed spectroscopically. We obtained independent spectroscopic
observations to determine its orbit, in addition to radio observations to see
if the thermal or non-thermal nature of the emission changes during the
periastron passage. We monitored HD 168112 spectroscopically for a 13 year time
span. From these data, we determined the orbital parameters, which we compared
to the previous results in the literature. From the spectral index of the radio
observations, we found how the nature of the emission changes as the system
goes through periastron. Combining our results with other literature data
allowed us to further constrain the orbital and stellar parameters. We find HD
168112 to have an orbital period of P = 512.17+0.41-0.11 d, an eccentricity of
e = 0.7533+0.0053-0.0124, and a mass ratio close to one. From our spectroscopic
modelling, we derived the stellar parameters, but we had difficulty arriving at
a spectroscopic mass ratio of one. The radio observations around periastron
show only thermal emission, suggesting that most of the synchrotron photons are
absorbed in the two stellar winds at that phase. Combining our data with the
optical interferometry detection, we could constrain the inclination angle to i
~ 63 deg, and the mass of each component to ~ 26 Msun. We have provided an
independent spectroscopic confirmation of the binary nature of HD 168112.
Although detected as a non-thermal radio emitter, near periastron the radio
emission of this highly eccentric system is thermal and is mainly formed in the
colliding-wind region. [abridged
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