bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of secular evolution on the star formation history of galaxies
Authors: Lorenzo M. Fernández , Sulentic J. , Verdes–Montenegro L. , Argudo-Fernández M. , Ruiz J. E. , Sabater J. , Sánchez–Expósito S. 
Published: March 2015

AbstractWe report the study performed as part of the AMIGA (Analysis of the interstellar Medium of Isolated GAlaxies; http://www.amiga.iaa.es) project, focused on the SDSS (g-r) colors of the sample. Assuming that color is an indicator of star formation history, this work better records the signature of passive star formation via pure secular evolution. Median values for each morphological type in AMIGA were compared with equivalent measures for galaxies in denser environments. We found a tendency for AMIGA spiral galaxies to be redder than galaxies in close pairs, but no clear difference when we compare with galaxies in other (e.g. group) environments. The (g-r) color of isolated galaxies presents a Gaussian distribution, as indicative of pure secular evolution, and a smaller median absolute deviation (almost half) compared to both wide and close pairs. This redder color and lower color dispersion of AMIGA spirals compared with close pairs is likely due to a more passive star formation in very isolated galaxies. In Fig. 1, we represent the size versus stellar mass for early and late–type galaxies of our sample, compared with the local relations of Shen et al. (2003). The late–type isolated galaxies are ~1.2 times larger or have less stellar mass than local spirals in other environments. The latter would be in agreement with the passive star formation found in the previous part.We acknowledge Grant AYA2011-30491-C02-01, P08-FQM-4205 and TIC-114.
Secular evolution in young galaxies
Authors: Elmegreen Bruce G. 
Published: March 2015

AbstractYoung galaxies viewed at high redshift have high turbulent velocities, high star formation rates, high gas fractions, and chaotic structures, suggesting wild instabilities during which giant gas clumps form and make stars in their dense regions, stir other disk stars and gas, and transport angular momentum outward with a resulting net mass flow inward (e.g., Ceverino et al.2010). At z=1.5, 40% of star-forming galaxies have significant clumps (Elmegreen et al.2007; Wuyts et al.2012), and in these, 10%-20% of the stellar mass is in clumps that last ~150 Myr (Elmegreen et al.2009; Wuyts et al.2012). The thick disk and bulge in modern galaxies could form in this phase. The similarity in the α/Fe ratio (Meléndez et al.2008), K-giant abundances (Bensby et al.2010) and ages for the Milky Way bulge and thick disk suggest they formed at the same time. High dispersion gas at z ~ 1.5 can do this because it makes the young disk thick and the SF clumps big enough to drive fast secular evolution (Elmegreen et al.2006; Genzel et al.2008; Bournaud et al.2009). Local analogues might be present in dynamically young galaxies like BCDs (Elmegreen et al.2012). The high fraction of z ~ 1.5 galaxies with massive clumps suggests clump formation is a long-lived phase and that clump torques should last ~ 1 Gyr or more even if individual clumps come and go on shorter timescales. Clump formation may cease when stars finally dominate the disk mass (Cacciato et al. 2012).
ALHAMBRA survey: morphological classification
Authors: Pović M. , Huertas-Company M. , Márquez I. , Masegosa J. , Aguerri J. A. López , Husillos C. , Molino A. , Cristóbal-Hornillos D. ,   ALHAMBRA team
Published: March 2015

AbstractThe Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey is a photometric survey designed to study systematically cosmic evolution and cosmic variance (Moles et al.2008). It employs 20 continuous medium-band filters (3500 - 9700 Å), plus JHK near-infrared (NIR) bands, which enable measurements of photometric redshifts with good accuracy. ALHAMBRA covers > 4 deg2 in eight discontinuous regions (~ 0.5 deg2 per region), of theseseven fields overlap with other extragalactic, multiwavelength surveys (DEEP2, SDSS, COSMOS, HDF-N, Groth, ELAIS-N1). We detect > 600.000 sources, reaching the depth of R(AB) ~ 25.0, and photometric accuracy of 2-4% (Husillos et al., in prep.). Photometric redshifts are measured using the Bayesian Photometric Redshift (BPZ) code (Benítez et al.2000), reaching one of the best accuracies up to date of δz/z ≤ 1.2% (Molino et al., in prep.).To deal with the morphological classification of galaxies in the ALHAMBRA survey (Pović et al., in prep.), we used the galaxy Support Vector Machine code (galSVM; Huertas-Company 2008, 2009), one of the new non-parametric methods for morphological classification, specially useful when dealing with low resolution and high-redshift data. To test the accuracy of our morphological classification we used a sample of 3000 local, visually classified galaxies (Nair & Abraham 2010), moving them to conditions typical of our ALHAMBRA data (taking into account the background, redshift and magnitude distributions, etc.), and measuring their morphology using galSVM. Finally, we measured the morphology of ALHAMBRA galaxies, obtaining for each source seven morphological parameters (two concentration indexes, asymmetry, Gini, M20 moment of light, smoothness, and elongation), probability if the source belongs to early- or late-type, and its error. Comparing ALHAMBRA morph COSMOS/ACS morphology (obtained with the same method) we expect to have qualitative separation in two main morphological types for ~ 20.000 sources in 8 ALHAMBRA fields. For early-type galaxies we expect to recover ~ 70% and 30-40% up to magnitudes 20.0 and 21.5, respectively, having the contamination of late-types of < 7%. For late-type galaxies, we expect to recover ~ 70%, 60 - 70%, and ~ 30% of sources up to magnitudes 22.0, 22.5, and 23.0, respectively, having the contamination of early-types of ≤ 10%. These data will be used to study the evolution of active and non-active galaxies respect to morphology and morphological properties of galaxies in groups and clusters.
Dust properties and magnetic field geometry towards LDN 1570
Authors: Eswaraiah C. , Maheswar G. , Pandey A. K. 
Published: March 2015

AbstractWe have performed both optical linear polarimetric and photometric observations of an isolated dark globule LDN 1570 aim to study the dust polarizing and extinction properties and to map the magnetic field geometry so as to understand not only the importance of magnetic fields in formation and evolution of clouds but also the correlation of the inferred magnetic field structure with the cloud structure and its dynamics. Dust size indicators (RV and λmax) reveal for the presence of slightly bigger dust grains towards the cloud region. The inferred magnetic field geometry, which closely follows the cloud structure revealed by Herschel images, suggest that the cloud could have been formed due to converging material flows along the magnetic field lines.
The modified equipartition calculation for supernova remnants with the spectral index α = 0.5
Authors: Urošević Dejan , Pavlović Marko Z. , Arbutina Bojan , Dobardžić Aleksandra 
Published: March 2015

AbstractRecently, the modified equipartition calculation for supernova remnants (SNRs) has been derived by Arbutina et al. (2012). Their formulae can be used for SNRs with the spectral indices between 0.5 < α < 1. Here, by using approximately the same analytical method, we derive the equipartition formulae useful for SNRs with spectral index α=0.5. These formulae represent next step upgrade of Arbutina et al. (2012) derivation, because among 30 Galactic SNRs with available observational parameters for the equipartition calculation, 16 have spectral index α = 0.5. For these 16 Galactic SNRs we calculated the magnetic field strengths which are approximately 40 per cent higher than those calculated by using Pacholczyk (1970) equipartition and similar to those calculated by using Beck & Krause (2005) calculation.
Science with Large Solar Telescopes: Overview of SpS 6
Authors: Cauzzi Gianna , Tritschler Alexandra , Deng Yuanyong 
Published: March 2015

AbstractWith several large aperture optical and IR telescopes just coming on-line, or scheduled for the near future, solar physics is on the verge of a quantum leap in observational capabilities. An efficient use of such facilities will require new and innovative approaches to both observatory operations and data handling.This two-days long Special Session discussed the science expected with large solar telescopes, and started addressing the strategies necessary to optimize their scientific return. Cutting edge solar science as derived from state-of-the-art observations and numerical simulations and modeling was presented, and discussions were held on the role of large facilities in satisfying the demanding requirements of spatial and temporal resolution, stray-light correction, and spectro-polarimetric accuracy. Building on the experience of recently commissioned telescopes, critical issues for the development of future facilities were discussed. These included operational issues peculiar to large telecopes as well as strategies for their best use.
The Near Earth Asteroid associations
Authors: Jopek Tadeusz J. 
Published: March 2015

AbstractWe have made an extensive search for grouping amongst the near Earth asteroids (NEAs). We used two D- functions and rigorous cluster analysis approach. We have found several new groups (associations) among the NEAs: the objects moving on similar orbits with small minimum orbital intersection distances (MOID) with the Earth trajectory. Reliability of some of these groups is quite high.
Selection effects in the discovery of NEAs
Authors: Valsecchi G. B. , D'Abramo G. , Boattini A. 
Published: March 2015

To highlight discovery selection effects, we consider four NEA subpopulations:
(a)“Taurid asteroids”, the Apollos with orbits similar to those of 2P/Encke and of the Taurid meteoroid complex;(b)Atens, to which we add the Inner Earth Objects;(c)non-Taurid Apollos;(d)Amors.
The “Taurid asteroids“ are identified by Asher et al. (1993) with a reduced version of the D-criterion (Southworth and Hawkins 1963), involving only a, e and i:

\begin{displaymath}
D=\sqrt{\left(\frac{a-2.1}{3}\right)^2+(e-0.82)^2+\left(2\sin{\frac{i-4^\circ}{2}}\right)^2}\leq0.25.
\end{displaymath}

It turns out that the distribution of the longitudes of perihelion ϖ of NEAs with D<0.25 is significantly non-random, due to the existence of two groups whose apse lines are approximately aligned with those of 2P/Encke and of (2212) Hephaistos.
The IAU Office of Astronomy for Development
Authors: Govender Kevin 
Published: March 2015

AbstractThe IAU Office of Astronomy for Development (OAD)†, established in March 2011 as part of the implementation of the IAU Strategic Plan, is currently located in South Africa and serves as a global coordinating centre for astronomy-for-development activities. In terms of structure the OAD is required to establish regional nodes (similar offices in different parts of the world which focus on a particular geographic or cultural region) and three task forces: (i) Astronomy for Universities and Research, (ii) Astronomy for Children and Schools, and (iii) Astronomy for the Public. This paper will describe the progress of the OAD towards the realisation of the vision ‘Astronomy for a better world’.
A project of a two meter telescope in North Africa
Authors: Benkhaldoun Zouhair 
Published: March 2015

AbstractSite testing undertaken during the last 20 years by Moroccan researchers through international studies have shown that the Atlas mountains in Morocco has potentialities similar to those sites which host the largest telescopes in world. Given the quality of the sites and opportunities to conduct modern research, we believe that the installation of a 2m diameter telescope will open new horizons for Astronomy in Morocco and north Africa allowing our region to enter definitively into the very exclusive club of countries possessing an instrument of that size. A state of the art astrophysical observatory on any good astronomical observation site should be equipped with a modern 2m-class, robotic telescope and some smaller telescopes. Our plan should be to operate one of the most efficient robotic 2m class telescopes worldwide in order to offer optimal scientific opportunities for researchers and maintain highest standards for the education of students. Beside all categories of astronomical research fields, students will have the possibility to be educated intensively on the design, manufacturing and operating of modern state of the art computer controlled instruments. In the frame of such education and observation studies several PhD and dissertational work packages are possible. Many of the observations will be published in articles worldwide and a number of guest observers from other countries will have the possibility to take part in collaborations. This could be a starting point of an international reputation of our region in the field of modern astronomy.
Galactic cold cores
Authors: Juvela M. ,   on behalf of the shape Planck and Herschel projects on cold cores
Published: March 2015

AbstractThe project Galactic Cold Cores is studying the early stages of Galactic star formation using far-infrared and sub-millimetre observations of dust emission. The Planck satellite has located many sources of cold dust emission that are likely to be pre-stellar clumps in interstellar clouds. We have mapped a sample of Planck-detected clumps with the Herschel satellite at wavelengths 100-500 μm. Herschel has confirmed the Planck detections of cold dust and have revealed a significant amount of sub-structure in the clumps. The cloud cores have colour temperatures in the range of 10–15 K. However, star formation is often already in progress with cold clumps coinciding with mid-infrared point sources. In less than half of the cases, the cloud morphology is clearly dominated by filamentary structures. The sources include both nearby isolated globules and more distant, massive clouds that may be off-the-plane counterparts of infrared dark clouds.The Herschel observations have been completed and the processed maps will be released to the community in 2013.
The coupled effects of protostellar outflows, radiation feedback, magnetic fields and turbulence on the formation of massive stars and Orion-like clusters
Authors: Klein Richard I. 
Published: March 2015

AbstractFeedback processes from massive stars plays a critical role in their formation, destroy the molecular clouds in which they are born and shape the evolution of galaxies. In this talk I will discuss our recent 3D AMR simulations that are the first to include the coupled feedback effects of protostellar outflows combined with protostellar heating and radiation pressure feedback and magnetic fields, in a single computation and their effects on the infalling dusty gas in the surrounding environs of the accreting core envelope. These simulations will address the detailed effects of feedback on the formation of high mass stars and massive clusters with implications for the IMF.
Dust and Molecule Formation and Processing in Supernovae and their Remnants
Authors: Rho J. , Andersen M. , Tappe A. , Gomez H. , Smith M. , Bernard J. P. , Onaka T. , Cami J. 
Published: March 2015

AbstractSupernovae (SNe) produce, fragment and destroy dust, molecules and nucleosynthetic elements, and reshape and modify the ISM. I will review recent infrared observations of supernova remnants (SNRs) and SNe which show that SNe are important sites of dust and molecule formation and are major dust creators in the Universe. Detection of carbon monoxide (CO) fundamental band from the young SNR Cas A indicates that astrochemical processes in SNRs interacting with molecular clouds provide astrophysical laboratories to study evolution of the ISM returning material from dense clouds into the more diffuse medium and galactic halo. Two dozen SNRs are known to be interacting with molecular clouds using H2 and millimeter observations. Recent Spitzer, Herschel and SOFIA observations along with ground-based observations have greatly advanced our understanding shock processing and astrochemistry of dust, H2, high J CO, and other neutral and ionized molecules and polycyclic aromatic hydrocarbon (PAH). Ionized molecules and warm layer of molecules that are excited by UV radiation, X-rays, or cosmic rays will be described. Finally I will discuss how astrochemical processes of dust and molecules in SNRs impact the large scale structures in the ISM.
Stellar wind and supernova feedback from massive stars
Authors: Pittard Julian M. , Rogers Hazel 
Published: March 2015

AbstractWe have constructed three-dimensional hydrodynamical models to simulate the impact of massive star feedback, via winds and SNe, on inhomogeneous molecular material left over from the formation of a massive stellar cluster. We are studying the timescales for the molecular material to be removed from the environment of a massive stellar cluster and the mass and energy fluxes into the wider environment.
Observational constraints on the multiphase ISM
Authors: Wolfire Mark G. 
Published: March 2015

AbstractIn recent years we have seen a wealth of new observations and analysis that sheds light on the distribution and physical properties of various ISM phases. In particular the thermal pressure from C I (Jenkins & Tripp 2011) shows the bulk of the CNM phase with a log normal pressure distribution. It appears that thermal instability is important for phase separation, but with with a thermal pressure variation about the mean driven by turbulence. In additional, there is evidence from C I, H2, and complex molecules, of both higher and lower pressure environments. An additional “phase“ that is of increasing interest for high z, low metallicity galaxies is the C+/H2 gas that is not traced by H I or CO. This review presents the observational evidence for the existence and physical properties of these various ISM phases.
Molecular richness of the diffuse interstellar medium: a signpost of turbulent dissipation
Authors: Falgarone Edith , Godard Benjamin , Forêts Guillaume Pineau des , Gerin Maryvonne 
Published: March 2015

AbstractThe Herschel/HIFI absorption spectroscopy surveys reveal the unexpected molecular richness of the Galactic diffuse ISM, even in gas of very low average H2 molecular fraction. In particular, two hydrides, CH+ and SH+ with highly endoenergetic formation routes have abundances that challenge models of UV-driven chemistry. The intermittent dissipation of turbulence appears as a plausible additional source of energy for the diffuse ISM chemistry. We present recent results of the so-called models of Turbulent Dissipation Regions (TDR). The abundances of many of the molecules observed in the diffuse ISM, including CO that is used as a tracer of the molecular clouds mass, may be understood in the framework of the TDR models.
Gravitational fragmentation of the Carina Flare supershell
Authors: Wünsch Richard 
Published: March 2015

AbstractWe study the gravitational fragmentation of a thick shell comparing the analytical theory to 3D hydrodynamic simulations and to observations of the Carina Flare supershell. We use both grid-based (AMR) and particle-based (SPH) codes to follow the idealised model of the fragmenting shell and found an excellent agreement between the two codes. Growth rates of fragments at different wavelength are well described by the pressure assisted gravitational instability (PAGI) - a new theory of the thick shell fragmentation. Using the APEX telescope we observe a part of the surface of the Carina Flare supershell (GSH287+04-17) in the 13CO(2–1) line. We apply a new clump-finding algorithm DENDROFIND to identify 50 clumps. We determine the clump mass function and we construct the minimum spanning tree connecting clumps positions to estimate the typical distance among clumps. We conclude that the observed masses and distances correspond well to the prediction of PAGI.
Statistical study of the ISM of GRB hosts
Authors: de Ugarte Postigo A. , Fynbo J. P. U. , Thöne C. C. , Christensen L. , Gorosabel J. , Sánchez-Ramírez R. 
Published: March 2015

AbstractGamma-ray burst (GRB) afterglows shine, during a brief period of time as the most luminous objects that can be detected in the Universe. They have been observed at almost any redshift, from our nearby environment (the nearest one, at z = 0.08) to the very distant Universe (the current record holder at z = 9.4). Their optical spectra are well reproduced by a clean, simple power law, making them ideal light houses to probe the interstellar medium of their host galaxies at any redshift. We have used the largest sample of GRB afterglow spectra collected to date to perform a statistical study of the interstellar medium in their host galaxies. By analysing the distribution of equivalent widths of the most prominent absorption features we evaluate the different types of environments that host GRBs and study their diversity.
Exploring science and technology through the Herschel space observatory
Authors: Minier V. , Rouzé M. 
Published: March 2015

AbstractBecause modern astronomy associates the quest of our origins and high-tech instruments, communicating and teaching astronomy explore both science and technology. We report here on our work in communicating astronomy to the public through Web sites (www.herschel.fr), movies on Dailymotion (www.dailymotion.com/AstrophysiqueTV) and new ITC tools that describe interactively the technological dimension of a space mission for astrophysics.
Hinode, the Sun, and public outreach
Authors: Yaji K. , Tonooka H. , Shimojo M. , Tokimasa N. , Suzuki D. , Nakamichi A. , Shimoikura I. 
Published: March 2015

Extended AbstractHinode is a solar observation satellite in Japan and its launch was in September 2006. Its name means “SUNRISE“ in Japanese. It has three instruments onboard in visible light, X-ray, EUV to solve mystery of coronal heating and origins of magnetic fields.Hinode has been providing us with impressive solar data, which are very important for not only investigating solar phenomena but also giving new knowledge about the sun to the public. In order to efficiently communicate Hinode data to the public, we organized working group for public use of Hinode data. which are composed of both researchers and educators in collaboration. As follow, we introduce our activities in brief.For the public use of Hinode data, at first, we produced two DVDs introducing Hinode observation results. In particular, second DVD contains a movie for kids, which are devloped to picturebook. Now, it is under producing an illustrated book and a planetarium program. It turn out that the DVDs help the public understand the sun from questionnaire surveys. Second, we developed teaching materials from Hinode data and had a science classroom about the sun, solar observations, practice with PC such as imaging software at junior high school. As the results, they had much interests in Hinode data. Third, we have joint observations with high school students and so on in a few years. The students compare their own data with Hinode data and have a presentation at science contests. The joint observations make their motivation higher in their activities.It is important to record and report our activities in some ways. So, we positively publish papers and have presentions in domestic/international meetings. Though we are supported in budget, resources and so on by NAOJ Hinode Team, we apply research funds for promoting our EPO activities and acquire some funds such as NAOJ Joint Research Expenses and Grands-Aid for Scientific Research Funds since the launch.This way, since its launch, we have continued various and constant EPO activities for the public use of Hinode data and have been giving intense impacts and high interest to the public. As the result, our activities contribute in further extension of Hinode Mission. Those are quite unique and would be reference of other similar ones. Hinode is now operating and solar activities might get more higher.As long as SUN RISE, we would GO FORWARD!!