80 research outputs found
Characterisation of night-time outdoor lighting in urban centres using cluster analysis of remotely sensed light emissions
Evidence of the negative impact of light pollution on ecosystems is
increasing every year. Its monitoring and study requires the identification,
characterisation and control of the emitting sources. This is the case of urban
centres with outdoor lighting that spills light outside the place it is
intended to illuminate. The quantity and nature of the pollutant (artificial
light at night) depends on the lamps used and how they are positioned. This is
important because a greater proportion of blue light means a greater scattering
effect. In this study, we analysed the emissions of 100 urban centres in the
north of Granada province (Spain), using International Space Station (ISS)
images from 2012 and 2021, in order to compare the results with public lighting
inventories and verify the validity of these data for characterising night-time
lighting emissions. Using inference and cluster analysis techniques, we
confirmed an overall increase in emissions and a shift in their colour towards
blue, consistent with the results of the lighting inventory analysis. We
concluded that it is possible to use ISS imagery to characterise artificial
light emissions and the lighting that causes them, none the less there are a
number of inherent problems with the data and the way it was collected that
require the results to be interpreted with caution
CARMENES input catalog of M dwarfs: VII. New rotation periods for the survey stars and their correlations with stellar activity
Abridged: We measured photometric and spectroscopic for a large
sample of nearby bright M dwarfs with spectral types from M0 to M9, as part of
our continual effort to fully characterize the Guaranteed Time Observation
programme stars of the CARMENES survey. We determine for 129
stars. Combined with the literature, we tabulate for 261 stars,
or 75% of our sample. We evaluate the plausibility of all periods available for
this sample by comparing them with activity signatures and checking for
consistency between multiple measurements. We find that 166 of these stars have
independent evidence that confirmed their . There are
inconsistencies in 27 periods, which we classify as debated. A further 68
periods are identified as provisional detections that could benefit from
independent verification. We provide an empirical relation for the uncertainty as a function of the value, based on the
dispersion of the measurements. We show that published formal errors seem to be
often underestimated for periods d. We highlight the importance of
independent verification on measurements, especially for inactive
M dwarfs. We examine rotation-activity relations with emission in X-rays,
H, Ca II H & K, and surface magnetic field strengths. We find overall
agreement with previous works, as well as tentative differences in the
partially versus fully convective subsamples. We show as a
function of stellar mass, age, and galactic kinematics. With the notable
exception of three transiting planet systems and TZ Ari, all known planet hosts
in this sample have d. This indicates that important
limitations need to be overcome before the radial velocity technique can be
routinely used to detect and study planets around young and active stars.Comment: Accepted for publication in A&
GRB 021004 modelled by multiple energy injections
GRB 021004 is one of the best sampled gamma-ray bursts (GRB) to date,
although the nature of its light curve is still being debated. Here we present
a large amount (107) of new optical, near-infrared (NIR) and millimetre
observations, ranging from 2 hours to more than a year after the burst. Fitting
the multiband data to a model based on multiple energy injections suggests that
at least 7 refreshed shocks took place during the evolution of the afterglow,
implying a total energy release (collimated within an angle of 1.8 deg) of ~
8x10^51 erg. Analysis of the late photometry reveals that the GRB 021004 host
is a low extinction (Av ~ 0.1) starburst galaxy with M_B ~ -22.0.Comment: 9 pages, 5 figures, accepted for publication in A&A
The CARMENES search for exoplanets around M dwarfs
Context. The CARMENES instrument, installed at the 3.5 m telescope of the Calar Alto Observatory in Almería, Spain, was conceived to deliver high-accuracy radial velocity (RV) measurements with long-term stability to search for temperate rocky planets around a sample of nearby cool stars. Moreover, the broad wavelength coverage was designed to provide a range of stellar activity indicators to assess the nature of potential RV signals and to provide valuable spectral information to help characterise the stellar targets.
Aims: We describe the CARMENES guaranteed time observations (GTO), spanning from 2016 to 2020, during which 19 633 spectra for a sample of 362 targets were collected. We present the CARMENES Data Release 1 (DR1), which makes public all observations obtained during the GTO of the CARMENES survey.
Methods: The CARMENES survey target selection was aimed at minimising biases, and about 70% of all known M dwarfs within 10 pc and accessible from Calar Alto were included. The data were pipeline-processed, and high-level data products, including 18 642 precise RVs for 345 targets, were derived. Time series data of spectroscopic activity indicators were also obtained.
Results: We discuss the characteristics of the CARMENES data, the statistical properties of the stellar sample, and the spectroscopic measurements. We show examples of the use of CARMENES data and provide a contextual view of the exoplanet population revealed by the survey, including 33 new planets, 17 re-analysed planets, and 26 confirmed planets from transiting candidate follow-up. A subsample of 238 targets was used to derive updated planet occurrence rates, yielding an overall average of 1.44 ± 0.20 planets with 1 M⊕ < Mpl sin i < 1000 M⊕ and 1 day < Porb < 1000 days per star, and indicating that nearly every M dwarf hosts at least one planet. All the DR1 raw data, pipeline-processed data, and high-level data products are publicly available online.
Conclusions: CARMENES data have proven very useful for identifying and measuring planetary companions. They are also suitable for a variety of additional applications, such as the determination of stellar fundamental and atmospheric properties, the characterisation of stellar activity, and the study of exoplanet atmospheres
The CARMENES search for exoplanets around M dwarfs. Two temperate Earth-mass planet candidates around Teegarden’s Star
Context.Teegarden’s Star is the brightest and one of the nearest ultra-cool dwarfs in the solar neighbourhood. For its late spectral type (M7.0 V),the star shows relatively little activity and is a prime target for near-infrared radial velocity surveys such as CARMENES.Aims.As part of the CARMENES search for exoplanets around M dwarfs, we obtained more than 200 radial-velocity measurements of Teegarden’sStar and analysed them for planetary signals.Methods.We find periodic variability in the radial velocities of Teegarden’s Star. We also studied photometric measurements to rule out stellarbrightness variations mimicking planetary signals.Results.We find evidence for two planet candidates, each with 1.1M⊕minimum mass, orbiting at periods of 4.91 and 11.4 d, respectively. Noevidence for planetary transits could be found in archival and follow-up photometry. Small photometric variability is suggestive of slow rotationand old age.Conclusions.The two planets are among the lowest-mass planets discovered so far, and they are the first Earth-mass planets around an ultra-cooldwarf for which the masses have been determined using radial velocities.We thank the referee Rodrigo Díaz for a careful review andhelpful comments. M.Z. acknowledges support from the Deutsche Forschungs-gemeinschaft under DFG RE 1664/12-1 and Research Unit FOR2544 “BluePlanets around Red Stars”, project no. RE 1664/14-1. CARMENES isan instrument for the Centro Astronómico Hispano-Alemán de Calar Alto(CAHA, Almería, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de InvestigacionesCientíficas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut für Astronomie, Instituto de Astrofísica de Andalucía, LandessternwarteKönigstuhl, Institut de Ciències de l’Espai, Institut für Astrophysik Göttingen,Universidad Complutense de Madrid, Thüringer Landessternwarte Tautenburg,Instituto de Astrofísica de Canarias, Hamburger Sternwarte, Centro de Astro-biología and Centro Astronómico Hispano-Alemán), with additional contribu-tions by the Spanish Ministry of Economy, the German Science Foundationthrough the Major Research Instrumentation Programme and DFG ResearchUnit FOR2544 “Blue Planets around Red Stars”, the Klaus Tschira Stiftung, thestates of Baden-Württemberg and Niedersachsen, and by the Junta de Andalucía.Based on data from the CARMENES data archive at CAB (INTA-CSIC). Thisarticle is based on observations made with the MuSCAT2 instrument, devel-oped by ABC, at Telescopio Carlos Sánchez operated on the island of Tener-ife by the IAC in the Spanish Observatorio del Teide. Data were partly col-lected with the 150-cm and 90-cm telescopes at the Sierra Nevada Observa-tory (SNO) operated by the Instituto de Astrofísica de Andalucía (IAA-CSIC).Data were partly obtained with the MONET/South telescope of the MOnitoringNEtwork of Telescopes, funded by the Alfried Krupp von Bohlen und HalbachFoundation, Essen, and operated by the Georg-August-Universität Göttingen,the McDonald Observatory of the University of Texas at Austin, and the SouthAfrican Astronomical Observatory. We acknowledge financial support from theSpanish Agencia Estatal de Investigación of the Ministerio de Ciencia, Inno-vación y Universidades and the European FEDER/ERF funds through projectsAYA2015-69350-C3-2-P, AYA2016-79425-C3-1/2/3-P, AYA2018-84089, BES-2017-080769, BES-2017-082610, ESP2015-65712-C5-5-R, ESP2016-80435-C2-1/2-R, ESP2017-87143-R, ESP2017-87676-2-2, ESP2017-87676-C5-1/2/5-R, FPU15/01476, RYC-2012-09913, the Centre of Excellence ”Severo Ochoa”and ”María de Maeztu” awards to the Instituto de Astrofísica de Canarias (SEV-2015-0548), Instituto de Astrofísica de Andalucía (SEV-2017-0709), and Cen-tro de Astrobiología (MDM-2017-0737), the Generalitat de Catalunya throughCERCA programme”, the Deutsches Zentrum für Luft- und Raumfahrt throughgrants 50OW0204 and 50OO1501, the European Research Council through grant694513, the Italian Ministero dell’instruzione, dell’università de della ricerca andUniversità degli Studi di Roma Tor Vergata through FFABR 2017 and “Mis-sion: Sustainability 2016”, the UK Science and Technology Facilities Council through grant ST/P000592/1, the Israel Science Foundation through grant848/16, the Chilean CONICYT-FONDECYT through grant 3180405, the Mexi-can CONACYT through grant CVU 448248, the JSPS KAKENHI through grantsJP18H01265 and 18H05439, and the JST PRESTO through grant JPMJPR1775
CALIFA, the Calar Alto Legacy Integral Field Area survey III. Second public data release
CALIFA is the first legacy survey being performed at Calar Alto. The CALIFA collaboration would like to thank the IAA-CSIC and MPIA-MPG as major partners of the observatory, and CAHA itself, for the unique access to telescope time and support in manpower and infrastructures. The CALIFA collaboration thanks also the CAHA staff for the dedication to this project. R.G.B., R.G.D., and E.P. are supported by the Spanish Ministerio de Ciencia e Innovacion under grant AYA2010-15081. S.Z. is supported by the EU Marie Curie Integration Grant "SteMaGE" Nr. PCIG12-GA-2012-326466 (Call Identifier: FP7-PEOPLE-2012 CIG). J.F.B. acknowledges support from grants AYA2010-21322-C03-02 and AIB-2010-DE-00227 from the Spanish Ministry of Economy and Competitiveness (MINECO), as well as from the FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA grant agreement number 289313. Support for L.G. is provided by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC12009, awarded to The Millennium Institute of Astrophysics, M.A.S.L.G. also acknowledges support by CONICYT through FONDECYT grant 3140566. A.G. acknowledges support from the FP7/2007-2013 under grant agreement n. 267251 (AstroFIt). J.M.G. acknowledges support from the Fundacao para a Ciencia e a Tecnologia (FCT) through the Fellowship SFRH/BPD/66958/2009 from FCT (Portugal) and research grant PTDC/FIS-AST/3214/2012. RAM was funded by the Spanish programme of International Campus of Excellence Moncloa (CEI). J.M.A. acknowledges support from the European Research Council Starting Grant (SEDmorph; P.I. V. Wild). I.M., J.M. and A.d.O. acknowledge the support by the projects AYA2010-15196 from the Spanish Ministerio de Ciencia e Innovacion and TIC 114 and PO08-TIC-3531 from Junta de Andalucia. AMI acknowledges support from Agence Nationale de la Recherche through the STILISM project (ANR-12-BS05-0016-02). M.M. acknowledges financial support from AYA2010-21887-C04-02 from the Ministerio de Economia y Competitividad. P.P. is supported by an FCT Investigador 2013 Contract, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). P.P. acknowledges support by FCT under project FCOMP-01-0124-FEDER-029170 (Reference FCT PTDC/FIS-AST/3214/2012), funded by FCT-MEC (PIDDAC) and FEDER (COMPETE). T.R.L. thanks the support of the Spanish Ministerio de Educacion, Cultura y Deporte by means of the FPU fellowship. PSB acknowledges support from the Ramon y Cajal program, grant ATA2010-21322-C03-02 from the Spanish Ministry of Economy and Competitiveness (MINECO). C.J.W. acknowledges support through the Marie Curie Career Integration Grant 303912. V.W. acknowledges support from the European Research Council Starting Grant (SEDMorph P.I. V. Wild) and European Career Re-integration Grant (Phiz-Ev P.I.V. Wild). Y.A. acknowledges financial support from the Ramon y Cajal programme (RyC-2011-09461) and project AYA2013-47742-C4-3-P, both managed by the Ministerio de Economia y Competitividad, as well as the "Study of Emission-Line Galaxies with Integral-Field Spectroscopy" (SELGIFS) programme, funded by the EU (FP7-PEOPLE-2013-IRSES-612701) within the Marie-Sklodowska-Curie Actions scheme. We thank the referee David Wilman for very useful comments that improved the presentation of the paper.This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects
are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph
PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto observatory. Two different spectral setups are available for each galaxy, (i) a lowresolution V500 setup covering the wavelength range 3745–7500 Å with a spectral resolution of 6.0 Å (FWHM); and (ii) a medium-resolution
V1200 setup covering the wavelength range 3650–4840 Å with a spectral resolution of 2.3 Å (FWHM). The sample covers a redshift range between
0.005 and 0.03, with a wide range of properties in the color–magnitude diagram, stellar mass, ionization conditions, and morphological types. All
the cubes in the data release were reduced with the latest pipeline, which includes improved spectrophotometric calibration, spatial registration,
and spatial resolution. The spectrophotometric calibration is better than 6% and the median spatial resolution is 200 : 4. In total, the second data
release contains over 1.5 million spectra.Instituto de Salud Carlos III
Spanish Government
AYA2010-15081
AYA2010-15196European Union (EU)
PCIG12-GA-2012-326466Spanish Ministry of Economy and Competitiveness (MINECO)
AYA2010-21322-C03-02
AIB-2010-DE-00227FP7 Marie Curie Actions of the European Commission, via the Initial Training Network DAGAL under REA
289313Ministry of Economy, Development, and Tourism's Millennium Science Initiative
IC12009Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)
CONICYT FONDECYT
3140566Fundacao para a Ciencia e a Tecnologia (FCT) from FCT (Portugal)
SFRH/BPD/66958/2009Spanish programme of International Campus of Excellence Moncloa (CEI)European Research Council (ERC)Junta de Andalucia
TIC 114
PO08-TIC-3531French National Research Agency (ANR)
ANR-12-BS05-0016-02Spanish Government
AYA2010-21887-C04-02FCT Investigador Contract - FCT/MCTES (Portugal)European Commission Joint Research Centre
European Social Fund (ESF)FCT - FCT-MEC (PIDDAC)
FCOMP-01-0124-FEDER-029170
FCT PTDC/FIS-AST/3214/2012European Union (EU)Spanish Ministerio de Educacion, Cultura y Deporte by FPURamon y Cajal program from the Spanish Ministry of Economy and Competitiveness (MINECO)
ATA2010-21322-C03-02European Union (EU)
303912European Career Re-integration GrantSpanish Government
RyC-2011-09461
AYA2013-47742-C4-3-PEuropean Union (EU)
FP7-PEOPLE-2013-IRSES-612701PTDC/FIS-AST/3214/2012Science & Technology Facilities Council (STFC)
ST/K000985/
The CARMENES search for exoplanets around M dwarfs High-resolution optical and near-infrared spectroscopy of 324 survey stars
The CARMENES radial velocity (RV) survey is observing 324 M dwarfs to search for any orbiting planets. In this paper, we present the survey sample by publishing one CARMENES spectrum for each M dwarf. These spectra cover the wavelength range 520–1710 nm at a resolution of at least R >80 000, and we measure its RV, Hα emission, and projected rotation velocity. We present an atlas of high-resolution M-dwarf spectra and compare the spectra to atmospheric models. To quantify the RV precision that can be achieved in low-mass stars over the CARMENES wavelength range, we analyze our empirical information on the RV precision from more than 6500 observations. We compare our high-resolution M-dwarf spectra to atmospheric models where we determine the spectroscopic RV information content, Q, and signal-to-noise ratio. We find that for all M-type dwarfs, the highest RV precision can be reached in the wavelength range 700–900 nm. Observations at longer wavelengths are equally precise only at the very latest spectral types (M8 and M9). We demonstrate that in this spectroscopic range, the large amount of absorption features compensates for the intrinsic faintness of an M7 star. To reach an RV precision of 1 m s−1 in very low mass M dwarfs at longer wavelengths likely requires the use of a 10 m class telescope. For spectral types M6 and earlier, the combination of a red visual and a near-infrared spectrograph is ideal to search for low-mass planets and to distinguish between planets and stellar variability. At a 4 m class telescope, an instrument like CARMENES has the potential to push the RV precision well below the typical jitter level of 3–4 m s−1
Trends and outcome of neoadjuvant treatment for rectal cancer: A retrospective analysis and critical assessment of a 10-year prospective national registry on behalf of the Spanish Rectal Cancer Project
Introduction: Preoperative treatment and adequate surgery increase local control in rectal cancer. However, modalities and indications for neoadjuvant treatment may be controversial. Aim of this study was to assess the trends of preoperative treatment and outcomes in patients with rectal cancer included in the Rectal Cancer Registry of the Spanish Associations of Surgeons.
Method: This is a STROBE-compliant retrospective analysis of a prospective database. All patients operated on with curative intention included in the Rectal Cancer Registry were included. Analyses were performed to compare the use of neoadjuvant/adjuvant treatment in three timeframes: I)2006–2009; II)2010–2013; III)2014–2017. Survival analyses were run for 3-year survival in timeframes I-II.
Results: Out of 14, 391 patients, 8871 (61.6%) received neoadjuvant treatment. Long-course chemo/radiotherapy was the most used approach (79.9%), followed by short-course radiotherapy ± chemotherapy (7.6%). The use of neoadjuvant treatment for cancer of the upper third (15-11 cm) increased over time (31.5%vs 34.5%vs 38.6%, p = 0.0018). The complete regression rate slightly increased over time (15.6% vs 16% vs 18.5%; p = 0.0093); the proportion of patients with involved circumferential resection margins (CRM) went down from 8.2% to 7.3%and 5.5% (p = 0.0004). Neoadjuvant treatment significantly decreased positive CRM in lower third tumors (OR 0.71, 0.59–0.87, Cochrane-Mantel-Haenszel P = 0.0008). Most ypN0 patients also received adjuvant therapy. In MR-defined stage III patients, preoperative treatment was associated with significantly longer local-recurrence-free survival (p < 0.0001), and cancer-specific survival (p < 0.0001). The survival benefit was smaller in upper third cancers.
Conclusion: There was an increasing trend and a potential overuse of neoadjuvant treatment in cancer of the upper rectum. Most ypN0 patients received postoperative treatment. Involvement of CRM in lower third tumors was reduced after neoadjuvant treatment. Stage III and MRcN + benefited the most
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