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Numrering	Referens	Omslagsbild	Hitta
1.	Aalto, Susanne, 1964 (författare) Astrochemistry and star formation in nearby galaxies: From galaxy disks to hot nuclei 2016 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759820221 ; 75-76, s. 73-80 Konferensbidrag (refereegranskat)abstract Studying the molecular phase of the interstellar medium in galaxies is fundamental for the understanding of the onset and evolution of compact and extended star formation, and of the growth of supermassive black holes. Molecular line emission is an excellent tracer of chemical, physical and dynamical conditions in the cold neutral gas. Key molecules in extragalactic studies are e.g. HCN, HCO+, HC3N, SiO, CH3OH, H2O. Furthermore, we can use IR excited molecular emission to probe the very inner regions of luminous infrared galaxies allowing us to get past the optically thick dust barrier of the compact obscured nuclei where lines of CO, HCN and HCO+ in their vibrational ground state (?=0) may be self-absorbed. Finally, molecular outflows and their chemistry are briefly discussed-including new ALMA results on for example the outflow of the lenticular galaxy NGC1377 and a study of the chemistry of the outflow of the quasar Mrk231.
2.	Baan, Willem A., et al. (författare) Dense Molecular Gas in Luminous Infrared Galaxies: Diagnosing the ISM 2008 Ingår i: EAS Publications Series. - : EAS, EDP Sciences. - 1633-4760 .- 1638-1963. ; 31, s. 111-114 Tidskriftsartikel (refereegranskat)abstract The behavior of molecular tracers of the high-density star-forming ISM provides a diagnostics tool for luminous FIR galaxies. All molecules react differently to the physical and chemical environment and their collective behavior is indicative of the excitation of the ISM and its evolutionary state. This paper describes efforts to diagnose the nuclear medium through multiple-molecule studies.
3.	Costagliola, Francesco, 1981, et al. (författare) Exploring the molecular chemistry and excitation in obscured LIRGs: An ALMA mm-wave spectral scan of NGC 4418 2016 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759820221 ; 75-76, s. 67-68 Konferensbidrag (refereegranskat)abstract The compact, obscured nuclei (CON) of luminous infrared galaxies (LIRG) combine large molecular columns with intense infrared (IR), ultra-violet (UV), and X-radiation and represent ideal laboratories for the study of the chemistry of the interstellar medium (ISM) under extreme conditions. Here we present the first ALMA wide-band spectral scan of a dusty LIRG, the CON NGC 4418. We derive molecular abundances and compare them with other Galactic and extragalactic sources. Our spectral scan confirms that the chemical complexity in the nucleus of NGC 4418 is one of the highest ever observed outside our Galaxy. We suggest that the galaxy may be a template for a new kind of chemistry and excitation, typical of CON.
4.	Edgar, Brian, 1945-, et al. (författare) The new potential for the Weyl tensor in n dimensions : wave equation and gauge 2008 Ingår i: Spanish Relativity Meeting 2007,2007. - Spain : EDR. ; , s. 245-248 Konferensbidrag (refereegranskat)abstract Although the Lanczos potential (a (2,1) form, L) for the Weyl tensor does not exist in dimensions greater than four, a new potential (a (2,3) form, P, which coincides with the double dual of L in four dimensions) has recently been shown to exist in all dimensions. In this talk we discuss the structure of its wave equation which is obtained from the Bianchi identities, and the related question of gauge.
5.	Farzone, M., et al. (författare) What is the origin of the water vapour signatures in red giant stars? 2013 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759809974 ; 60, s. 155-159 Konferensbidrag (refereegranskat)abstract We investigate the occurrence of water vapour signatures in a total of 10 red giants in the solar neighbourhood at mid-infrared wavelengths (12 pm). With the use of high resolution spectra from TEXES and synthesized spectra based on MARCS model atmospheres, we analyse the differences and discuss plausible causes. These include abundance adjustments, the addition of non-photospheric components (MOLspheres) and a different temperature profile.
6.	Feiden, Gregory, 1986-, et al. (författare) Magnetic Field Induced Radius Inflation of Low-Mass Stars 2013 Ingår i: Binary 2013: Setting a new standard in the analysis of binary stars.. - : EDP Sciences. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract We present results obtained using the magnetic Dartmouth stellar evolution code that address the possibility that magnetic fields are inflating low-mass stars in detached eclipsing binaries. While it seems plausible that magnetic fields are inflating stars with radiative cores, the level of inflation observed among fully convective stars appears too large to be explained by magnetic fields. We provide an alternative explanation, stellar metallicity, and propose observations that can help further constrain stellar models.
7.	Holl, Berry, et al. (författare) Characterizing the Astrometric Errors in the Gaia Catalogue 2011 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 45:GAIA: At the Frontiers of Astrometry, s. 117-122 Tidskriftsartikel (refereegranskat)abstract Accurate characterization of the errors in the global astrometric solution for Gaia is essential for making optimal use of the catalogue data. We investigate the structure of the covariance between the estimated astrometric parameters by studying the properties of the astrometric least squares solution. We find that astrometric errors can be separated in a star and an attitude part, due to the estimation of the star and attitude parameters respectively. Hence the covariances can be separated in a star, an attitude and a cross term. This is demonstrated using our scalable simulation tool AGISLab, where the covariances are estimated statistically using Monte Carlo techniques.
8.	Lammers, U., et al. (författare) News on Seeking Gaia's Astrometric Core Solution with AGIS 2011 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 45:GAIA: At the Frontiers of Astrometry, s. 123-126 Tidskriftsartikel (refereegranskat)abstract We report on recent new developments around the Astrometric Global Iterative Solution system. This includes the availability of an efficient Conjugate Gradient solver and the Generic Astrometric Calibration scheme that had been proposed a while ago. The number of primary stars to be included in the core solution is now believed to be significantly higher than the 100 Million that served as baseline until now. Cloud computing services are being studied as a possible cost-effective alternative to running AGIS on dedicated computing hardware at ESAC during the operational phase.
9.	Lindegren, Lennart, et al. (författare) Basic principles of scanning space astrometry 2011 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 45:GAIA: At the Frontiers of Astrometry, s. 109-114 Tidskriftsartikel (refereegranskat)abstract We outline the basic principles of scanning space astrometry, such as represented by Hipparcos, Gaia, and some other astrometric satellites planned or proposed. We explain the need for large-angle measurements, why these are essentially one-dimensional, how it is possible to determine absolute parallaxes, and why a Hipparcos-type scanning law is favourable. We discuss the choice of the basic angle between the two viewing directions, the principle of self-calibration, and why the resulting numerical problem must be difficult to solve.
10.	Lindegren, Lennart (författare) ELSA and Gaia: Four years of fruitful collaboration 2011 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 45:GAIA: At the Frontiers of Astrometry, s. 3-8 Tidskriftsartikel (refereegranskat)abstract ELSA (European Leadership in Space Astrometry) is a four-year, EU-funded Research Training Network ending in September 2010. It has employed 10 postgraduate students and 5 postdocs for 2-3 years and financed a number of workshops, training events and topical meetings, culminating in the present symposium. The primary goal of ELSA is to train young scientists in the context of the Gaia project while contributing to the scientific preparations for the mission. The organization, aims and history of ELSA are outlined.
11.	Liu, C., et al. (författare) Quest for the Sun's siblings based on elemental abundances 2014 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 67-68:January, s. 127-131 Tidskriftsartikel (refereegranskat)abstract We present stellar parameters, stellar ages, and detailed elemental abundances for Na, Mg, Al, Si, Ca, Ti, Cr, Fe, and Ni for 32 solar sibling candidates. Technique of chemical tagging gives us a high probability that four stars might be from the same open cluster. Only one candidate HIP 40317 which has solar metallicity and age could be a solar sibling. We performed simulations of the Sun's birth cluster in analytical Galactic model and found that there is quite low probability to find solar siblings with radial velocity up to Vr = 34.2 km s-1.
12.	Loenen, A. F., et al. (författare) Extragalactic Chemistry: HCN, HNC, and HCO+ : M. , W. A. Baan, and R. 2008 Ingår i: EAS Publications Series. - : EAS, EDP Sciences. - 1633-4760 .- 1638-1963. ; 31, s. 183-185 Tidskriftsartikel (refereegranskat)abstract High- and low-density tracer molecules have been observed in (Ultra-) Luminous Infrared Galaxies in order to initiate multi-molecule multi-transition studies to evaluate the physical and chemical environment of the nuclear medium and the ongoing nuclear activity. The data, augmented with data available in the literature, are presented in Baan et al. (2007), which also presents a first order analysis. Here, we present the chemical analysis of the J=1–0 transition lines of HCN, HNC, and HCO+.
13.	Lombaert, Robin, 1986, et al. (författare) The Problematically Short Superwind of OH/IR Stars 2015 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759819072 ; 71-72, s. 65-70 Konferensbidrag (refereegranskat)abstract The superwind is believed to be the tool with which stars with an intermediate main-sequence mass between 5 and 8 Me shed most of their stellar mantle to evolve from the asymptotic giant branch (AGB) into the post-AGB and planetary-nebulae stages. For this to work, the superwind duration must be on the order of at least ten thousand years given a mass-loss rate of 10(-4) M-circle dot per year. This contrasts heavily with recent, independent results indicating that the superwind duration may be shorter by an order of magnitude.
14.	Lykou, F., et al. (författare) Unraveling Disks in AGB Stars 2015 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759819072 ; 71-72, s. 217-222 Konferensbidrag (refereegranskat)abstract It is commonly accepted that asymmetries found in the post-AGB stars and planetary nebulae should originate as early as during the AGB phase. We present results from our high-angular resolution observing programs, with an aperture masking technique on the VLT, of a sample of evolved stars that were known to present asymmetries at larger spatial scales (e.g. jets, torii and/or bipolar nebulae). Disk-like structures have been found in the vicinity of at least two of these stars.
15.	Malmberg, Daniel, et al. (författare) Making Extrasolar Planets From Solar Systems Via Dynamical Interactions 2010 Ingår i: Extrasolar Planets In Multi-Body Systems: Theory And Observations. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 42, s. 375-383 Konferensbidrag (refereegranskat)abstract Most stars form in some sort of stellar cluster or association. In such environments the number density of stars is much higher than in the solar neighbourhood, which means that close encounters between stars may be relatively common. Using numerical simulations we quantify the fraction of single stars in the solar neighbourhood that have never suffered a close encounter or been part of a binary system. We call such stars singletons. Furthermore, we study what would happen to a solar-system-like planetary system if its host star was exchanged into a binary system during an exchange encounter in a young stellar cluster. The perturbation of the companion star might in such a system trigger strong planet-planet scatterings. This would subsequently lead to the ejection of one or more planets, leaving those remaining on tighter and more eccentric orbits. We find that only if the gas giants in solar-system-like planetary systems most often have rather similar masses does the resulting eccentricity distribution resemble that of the observed extrasolar planets.
16.	Mangum, J. G., et al. (författare) Densitometry and Thermometry of Starburst Galaxies 2016 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759820221 ; 75-76, s. 61-65 Konferensbidrag (refereegranskat)abstract With a goal toward deriving the physical conditions in external galaxies, we have conducted a survey and subsequent high spatial resolution imaging of formaldehyde (H2CO) and ammonia (NH3) emission and absorption in a sample of starburst galaxies. In this article we present the results from a subset of this survey which focuses on high spatial resolution measurements of volume density-and kinetic temperature-sensitive transitions of the H2CO molecule. The volume density structure toward the nuclear region of NGC 253 has been derived from ? â‰ 4 arcsec NRAO Very Large Array (VLA) measurements of the 110-111 and 211-212 K-doublet transitions of H2CO. The kinetic temperature structure toward NGC 253 and NGC 4945 has been derived from ? â‰ 0.5-1.0 arcsec measurements of the H2CO 3K-1K+1-2K-1K+1 (near 218 GHz) and 5K-1K+1-4K-1K+1 (near 365 GHz) transitions acquired using the Atacama Large Millimeter/submillimeter Array (ALMA). These measurements have allowed us to characterize the dense gas and kinetic temperature structure within these star forming galaxies, which is a first step toward associating dense star-forming gas and the heating processes at work within galaxies.
17.	Matsuura, M., et al. (författare) Detection of Rotational Co Emission from the Red-Supergiants in the Large Magellanic Cloud 2015 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759819072 ; 71-72, s. 53-56 Konferensbidrag (refereegranskat)abstract It is yet well understood how mass-loss rates from evolved stars depend on metallicities. With a half of the solar metallicity and the distance of only 50 kpc, the evolved stars of the Large Magellanic Cloud (LMC) are an ideal target for studying mass loss at low metallicity. We have obtained spectra of red-supergiants in the LMC, using the Hershel Space Observatory, detecting CO thermal lines fro J=6-5 up to 15-14 lines. Modelling CO lines with non-LTE Radiative transfer code suggests that CO lines intensities can be well explained with high gas-to-dust ratio, with no obvious reduction in mass-loss rate at the LMC. We conclude that the luminosities of the stars are dominant factors on mass-loss rates, rather than the metallicity.
18.	McMillan, P.~J. (författare) Making action-angle disc models for Gaia 2014 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 67, s. 79-82 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
19.	Mohamed, S., et al. (författare) 3d Models of Symbiotic Binaries 2015 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759819072 ; 71-72, s. 81-86 Konferensbidrag (refereegranskat)abstract Symbiotic binaries consist of a cool, mass-losing giant and an accreting, compact companion. We present 3D Smoothed Particle Hydrodynamics (SPH) models of two such interacting binaries, RS Oph and Mira AB. RS Oph is also a recurrent nova system, thus we model multiple quiescent mass transfer-nova outburst cycles. The resulting circumstellar structures of both systems are highly complex with the formation of spirals, arcs, shells, equatorial and bipolar outflows. We compare the models to recent observations and discuss the implications of our results for related systems, e.g., bipolar nebulae and jets, chemically peculiar stars, and the progenitors of Type Ia supernovae.
20.	Olofsson, Göran, 1944- (författare) The SPIRE Instrument 2009 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 34, s. 33-42 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract SPIRE, the Spectral and Photometric Imaging Receiver, is Herschel's submillimetre camera and spectrometer. It comprises a three-band imaging photometer operating at 250, 350 and 500 µm, and an imaging Fourier Transform Spectrometer (FTS) covering 194–672 µm. The design of SPIRE is described, and the expected scientific performance is summarised, based on modelling and flight instrument test results.
21.	Pérez-Beaupuits, J.P., et al. (författare) HNC and HCN in Seyfert Galaxies 2008 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 31, s. 195-196 Konferensbidrag (refereegranskat)abstract What are the physical conditions in the nuclear region of Seyfert galaxies? Can we asses the predominant nuclear source of power starburst or AGN by using high density gas tracers? We have used SEST, JCMT, and IRAM 30 m telescopes to observe the J=1-0, J=3-2, and J=4-3 transition lines of HNC and HCN in the Seyfert 2 galaxies NGC 1068 and NGC 3079. We model the excitatioon conditions of these molecules based on the observed 3–2/1–0 line intensity ratios. In these proceedings we show the line ratios and discuss the excitation conditions modeled. We summarize our results and conclusions as follows: in NGC 1068, the emission of HNC emerges from lower (<10^5 {cm-3}) density gas than HCN (>10^5 {cm-3}). Instead, the emission of HNC and HCN emerges from the same gas in NGC 3079. The observed HCN/HNC line ratios favor a PDR scenario rather than an XDR one. However, the N(HNC)/N(HCN) column density ratios obtained for NGC 3079 can be found only in XDR environments.
22.	Sarri, Gianluca, et al. (författare) Magnetic field suppression in collision-less shocks generated during the expansion of a dense plasma into a rarefied mediu 2013 Ingår i: EAS Publications Series. - : E D P Sciences. - 1633-4760 .- 1638-1963. - 9782759809417 ; 58, s. 33-36 Tidskriftsartikel (refereegranskat)abstract A two-dimensional numerical study of the expansion of a dense plasma through a more rarefied one is reported. The electrostatic ion-acoustic shock, which is generated during the expansion, accelerates the electrons of the rarefied plasma inducing a superthermal population which reduces electron thermal anisotropy. The Weibel instability is therefore not triggered and no self-generated magnetic fields are observed, in contrast with published theoretical results dealing with plasma expansion into vacuum.
23.	Schneider, N., et al. (författare) Atmospheric transmission at Dome C between 0 and 10 THz 2010 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 40, s. 327-332 Tidskriftsartikel (refereegranskat)abstract We present model calculations of the atmospheric transmission for DOME C in Antarctica for frequencies up to 10THz (30 μm) using the forward model MOLIERE-5. Measurements of precipitable water vapor (pwv), obtained by the SUMMIT radiometer installed at the Concordia station during 2008 and working at a wavelength of 200μm, are translated into atmospheric transmission using MOLIERE. Quartiles of transmission, calculated from 200μm data are extrapolated to 350 μm and compared to the CCAT (Cornell-Caltech Atacama Telescope) site in Chile. It turns out that for 25% of the time at DOME C (CCAT), the transmission is around 20% (5%) at 200μm. This corresponds to a pwv of 0.18mm for DOME C. At 350μm, for 50% of time at DOME C (CCAT) the transmission is around 55% (25%). This corresponds to a pwv of 0.22mm for DOME C. These results show that DOME C is one of the best observing sites on Earth for submm-astronomy with respect to high atmospheric transmission over long time periods
24.	Tremblin, P., et al. (författare) Dome C: The best accessible site on Earth for submillimetre astronomy 2010 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 40, s. 333-336 Tidskriftsartikel (refereegranskat)abstract We present preliminary results of the measurements of sky transparency conducted at Dome C during the winter 2008. Using MOLIERE modeling, we estimate a low precipitable water vapour content above Concordia station, which is very promising for future submillimetre wave observations on the Antarctic Plateau.
25.	Turon, Catherine, et al. (författare) Foreword 2011 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 45:GAIA: At the Frontiers of Astrometry Tidskriftsartikel (refereegranskat)
26.	Van De Sande, M., et al. (författare) Unraveling The Dust Formation Process In R DOR 2015 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. - 9782759819072 ; 71-72, s. 255-257 Konferensbidrag (refereegranskat)abstract Using both dynamical and chemical modelling, we derive an accurate abundance profile for the molecule SiO in the stellar wind of R Dor, an O-rich AGB star. SiO plays a key role in the dust formation process in O-rich AGB stars. This method will be applied to additional molecules, with the aim to achieve a detailed overview of the molecular abundance pattern in the wind of R Dor.
27.	Walton, N. A., et al. (författare) GREAT-ITN and Gaia : Preparing for Science 2014 Ingår i: EAS Publications Series. - : EDP Sciences. - 1633-4760 .- 1638-1963. ; 67-68:January, s. 7-14 Tidskriftsartikel (refereegranskat)abstract This paper gives a brief overview of the Gaia Research for European Astronomy Training (GREAT) network, including a description of the GREAT-ESF Research Network Programme and the GREAT Initial Training Network (GREAT-ITN). Scientific highlights from the GREAT-ITN are noted.
28.	Axelsson, Magnus (författare) Photospheric emission from gamma-ray bursts 2013 Ingår i: EAS Publications Series. - : EDP Sciences. - 1638-1963. ; , s. 53-57 Konferensbidrag (refereegranskat)abstract In spite of extensive research over the past decades, a complete physical picture of the origin of the prompt gamma-ray burst emission is still lacking. During recent years, evidence has been accumulating that the jet photosphere plays an important role. In this paper we summarize the lessons learned from Fermi observations regarding the behavior of the photosphere and discuss why photospheric emission does not necessarily appear as blackbody radiation. We concentrate on two strong and important bursts, GRB 090902B and GRB 110721A, which serve as examples of the standard appearance photospheric emission may have in gamma-ray burst spectra.
29.	Pidokrajt, Narit, 1979-, et al. (författare) On Geometro-thermodynamics of dilaton black holes 2008 Ingår i: EAS Publications Series. - France : EDP Sciences 2008. - 1638-1963. ; 30, s. 279-283 Tidskriftsartikel (refereegranskat)abstract In this talk we present the latest results from our ongoing project on geometro-thermodynamics (also known as information geometry of thermodynamics or Ruppeiner geometry) of dilaton BHs in 4D in both Einstein and string frames and a dyonic dilaton BH and at the end we report very briefly results from this approach to the 2D dilaton BHs.

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