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Author

G. Palacios-Navarro

Other affiliations: University of Cambridge
Bio: G. Palacios-Navarro is an academic researcher from University of Zaragoza. The author has contributed to research in topics: Computer science & Medicine. The author has an hindex of 3, co-authored 3 publications receiving 1253 citations. Previous affiliations of G. Palacios-Navarro include University of Cambridge.

Papers
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Journal ArticleDOI
Sebastián F. Sánchez1, Robert C. Kennicutt2, A. Gil de Paz3, G. van de Ven4, José M. Vílchez1, Lutz Wisotzki5, C. J. Walcher5, D. Mast1, J. A. L. Aguerri1, J. A. L. Aguerri6, Sergio Albiol-Pérez7, Almudena Alonso-Herrero1, João Alves8, J. Bakos1, J. Bakos6, T. Bartakova9, Joss Bland-Hawthorn10, Alessandro Boselli11, D. J. Bomans12, África Castillo-Morales3, C. Cortijo-Ferrero1, A. de Lorenzo-Cáceres6, A. de Lorenzo-Cáceres1, A. del Olmo1, Ralf-Jürgen Dettmar12, Angeles I. Díaz13, Simon Ellis14, Simon Ellis10, Jesús Falcón-Barroso6, Jesús Falcón-Barroso1, Hector Flores15, Anna Gallazzi16, Begoña García-Lorenzo6, Begoña García-Lorenzo1, R. M. González Delgado1, Nicolas Gruel, Tim Haines17, C. Hao18, Bernd Husemann5, J. Iglesias-Páramo1, Knud Jahnke4, Benjamin D. Johnson19, Bruno Jungwiert20, Bruno Jungwiert21, Veselina Kalinova4, C. Kehrig5, D. Kupko5, Angel R. Lopez-Sanchez22, Angel R. Lopez-Sanchez14, Mariya Lyubenova4, R. A. Marino1, R. A. Marino3, E. Mármol-Queraltó1, E. Mármol-Queraltó3, I. Márquez1, J. Masegosa1, Sharon E. Meidt4, Jairo Méndez-Abreu6, Jairo Méndez-Abreu1, Ana Monreal-Ibero1, C. Montijo1, A. Mourao23, G. Palacios-Navarro7, Polychronis Papaderos24, Anna Pasquali25, Reynier Peletier, Enrique Pérez1, I. Pérez26, Andreas Quirrenbach, M. Relaño26, F. F. Rosales-Ortega13, F. F. Rosales-Ortega1, Martin Roth5, T. Ruiz-Lara26, Patricia Sanchez-Blazquez13, C. Sengupta1, R. Singh4, Vallery Stanishev23, Scott Trager27, Alexandre Vazdekis6, Alexandre Vazdekis1, Kerttu Viironen1, Vivienne Wild28, Stefano Zibetti16, Bodo L. Ziegler8 
TL;DR: The Calar Alto Legacy Integral Field Area (CALIFA) survey as discussed by the authors was designed to provide a first step in this direction by obtaining spatially resolved spectroscopic information of a diameter selected sample of similar to 600 galaxies in the Local Universe.
Abstract: The final product of galaxy evolution through cosmic time is the population of galaxies in the local universe. These galaxies are also those that can be studied in most detail, thus providing a stringent benchmark for our understanding of galaxy evolution. Through the huge success of spectroscopic single-fiber, statistical surveys of the Local Universe in the last decade, it has become clear, however, that an authoritative observational description of galaxies will involve measuring their spatially resolved properties over their full optical extent for a statistically significant sample. We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction. We summarize the survey goals and design, including sample selection and observational strategy. We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of similar to 600 galaxies in the Local Universe (0.005 < z < 0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK integral field unit (IFU), with a hexagonal field-of-view of similar to 1.3 square', with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 angstrom, using two overlapping setups (V500 and V1200), with different resolutions: R similar to 850 and R similar to 1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis: (i) the final datacubes reach a 3 sigma limiting surface brightness depth of similar to 23.0 mag/arcsec(2) for the V500 grating data (similar to 22.8 mag/arcsec(2) for V1200); (ii) about similar to 70% of the covered field-of-view is above this 3 sigma limit; (iii) the data have a blue-to-red relative flux calibration within a few percent in most of the wavelength range; (iv) the absolute flux calibration is accurate within similar to 8% with respect to SDSS; (v) the measured spectral resolution is similar to 85 km s(-1) for V1200 (similar to 150 km s(-1) for V500); (vi) the estimated accuracy of the wavelength calibration is similar to 5 km s(-1) for the V1200 data (similar to 10 km s(-1) for the V500 data); (vii) the aperture matched CALIFA and SDSS spectra are qualitatively and quantitatively similar. Finally, we show that we are able to carry out all measurements indicated above, recovering the properties of the stellar populations, the ionized gas and the kinematics of both components. The associated maps illustrate the spatial variation of these parameters across the field, reemphasizing the redshift dependence of single aperture spectroscopic measurements. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.

1,143 citations

Journal ArticleDOI
TL;DR: The first public data release (DR1) of the Calar Alto Legacy Integral Field Area (CALIFA) survey is presented in this article, which consists of science-grade optical datacubes for the first 100 of eventually 600 nearby (0.005 < z < 0.03) galaxies, obtained with the integral field spectrograph PMAS/PPak mounted on the 3.5 m telescope at the Calal Alto observatory.
Abstract: We present the first public data release (DR1) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. It consists of science-grade optical datacubes for the first 100 of eventually 600 nearby (0.005 < z < 0.03) galaxies, obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto observatory. The galaxies in DR1 already cover a wide range of properties in color-magnitude space, morphological type, stellar mass, and gas ionization conditions. This offers the potential to tackle a variety of open questions in galaxy evolution using spatially resolved spectroscopy. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the nominal wavelength range 3745-7500 angstrom with a spectral resolution of 6.0 angstrom (FWHM), and (ii) a medium-resolution V1200 setup covering the nominal wavelength range 3650-4840 angstrom with a spectral resolution of 2.3 angstrom (FWHM). We present the characteristics and data structure of the CALIFA datasets that should be taken into account for scientific exploitation of the data, in particular the effects of vignetting, bad pixels and spatially correlated noise. The data quality test for all 100 galaxies showed that we reach a median limiting continuum sensitivity of 1.0 x 10(-18) erg s(-1) cm(-2) angstrom(-1) arcsec(-2) at 5635 angstrom and 2.2 x 10(-18) erg s(-1) cm(-2) angstrom(-1) arcsec(-2) at 4500 angstrom for the V500 and V1200 setup respectively, which corresponds to limiting r and g band surface brightnesses of 23.6 mag arcsec(-2) and 23.4 mag arcsec(-2), or an unresolved emission-line flux detection limit of roughly 1 x 10(-17) erg s(-1) cm(-2) arcsec(-2) and 0.6 x 10(-17) erg s(-1) cm(-2) arcsec(-2), respectively. The median spatial resolution is 3 ''.7, and the absolute spectrophotometric calibration is better than 15% (1 sigma). We also describe the available interfaces and tools that allow easy access to this first public CALIFA data at http://califa.caha.es/DR1.

251 citations

Journal ArticleDOI
Sebastián F. Sánchez1, Robert C. Kennicutt2, A. Gil de Paz3, G. van de Ven4, José M. Vílchez1, Lutz Wisotzki5, C. J. Walcher5, D. Mast1, J. A. L. Aguerri1, J. A. L. Aguerri6, Sergio Albiol-Pérez7, Almudena Alonso-Herrero1, João Alves8, J. Bakos6, J. Bakos1, T. Bartakova9, Joss Bland-Hawthorn10, Alessandro Boselli11, D. J. Bomans12, África Castillo-Morales3, C. Cortijo-Ferrero1, A. de Lorenzo-Cáceres6, A. de Lorenzo-Cáceres1, A. del Olmo1, Ralf-Jürgen Dettmar12, Angeles I. Díaz13, Simon Ellis14, Simon Ellis10, Jesús Falcón-Barroso1, Jesús Falcón-Barroso6, Hector Flores15, Anna Gallazzi16, Begoña García-Lorenzo6, Begoña García-Lorenzo1, R. M. González Delgado1, Nicolas Gruel, Tim Haines17, C. Hao18, Bernd Husemann5, J. Iglesias-Páramo1, Knud Jahnke4, Benjamin D. Johnson19, Bruno Jungwiert20, Bruno Jungwiert21, Veselina Kalinova4, C. Kehrig5, D. Kupko5, Angel R. Lopez-Sanchez22, Angel R. Lopez-Sanchez14, Mariya Lyubenova4, R. A. Marino3, R. A. Marino1, E. Mármol-Queraltó1, E. Mármol-Queraltó3, I. Márquez1, J. Masegosa1, Sharon E. Meidt4, Jairo Méndez-Abreu1, Jairo Méndez-Abreu6, Ana Monreal-Ibero1, C. Montijo1, A. Mourao23, G. Palacios-Navarro7, Polychronis Papaderos24, Anna Pasquali25, Reynier Peletier, Enrique Pérez1, I. Pérez26, Andreas Quirrenbach, M. Relaño26, F. F. Rosales-Ortega1, F. F. Rosales-Ortega13, Martin Roth5, T. Ruiz-Lara26, Patricia Sanchez-Blazquez13, C. Sengupta1, R. Singh4, Vallery Stanishev23, Scott Trager27, Alexandre Vazdekis1, Alexandre Vazdekis6, Kerttu Viironen1, Vivienne Wild28, Stefano Zibetti16, Bodo L. Ziegler8 
TL;DR: The Calar Alto Legacy Integral Field Area (CALIFA) survey as mentioned in this paper was designed to provide a first step in this direction, obtaining spatially resolved spectroscopic information of a diameter selected sample of galaxies in the Local Universe (0.005 < z < 0.03).
Abstract: We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction.We summarize the survey goals and design, including sample selection and observational strategy.We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of $\sim600$ galaxies in the Local Universe (0.005< z <0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK Integral Field Unit (IFU), with a hexagonal field-of-view of $\sim1.3\sq\arcmin'$, with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 A, using two overlapping setups (V500 and V1200), with different resolutions: R\sim850 and R\sim1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.

115 citations

Journal ArticleDOI
10 Sep 2022-Energies
TL;DR: This paper presents the development of a two-channel electrical parameter-monitoring system based on the M5 Stack Core2 kit, obtaining a low-cost compact product with multiple features.
Abstract: Energy monitors are indispensable for achieving efficient electrical grids and even more so in the age of the Internet of Things (IoT), where electrical system data are monitored from anywhere in the world. This paper presents the development of a two-channel electrical parameter-monitoring system based on the M5 Stack Core2 kit. The acquisition of variables is done through PZEM 004T V3.0 sensors, and the data are sent to the ThingSpeak cloud database. Local readings are done through the LCD, and data re stored on a micro SD card. Remote monitoring is done through two applications, namely a web application and a mobile application, each designed for different purposes. To validate this proposal, a commercial device with IoT features (Gen 2 Vue Energy Monitor) is used, comparing the active power and active energy readings recorded continuously for 7 days. The results indicate an accuracy of up to 1.95% in power and 0.81% in energy, obtaining a low-cost compact product with multiple features.

7 citations

Journal ArticleDOI
TL;DR: In this paper , the authors evaluated the effectiveness and usefulness of a task based on an activity of daily living (ADL) for the detection of cognitive impairment for an Alzheimer's disease (AD) population.
Abstract: There are conventional screening instruments for the detection of cognitive impairment, but they have a reduced ecological validity and the information they present could be biased. This study aimed at evaluating the effectiveness and usefulness of a task based on an activity of daily living (ADL) for the detection of cognitive impairment for an Alzheimer’s disease (AD) population. Twenty-four participants were included in the study. The AD group (ADG) included twelve older adults (12 female) with AD (81.75±7.8 years). The Healthy group (HG) included twelve older adults (5 males, 77.7 ± 6.4 years). Both groups received a ADL-based intervention at two time frames separated 3 weeks. Cognitive functions were assessed before the interventions by using the MEC-35. The test-retest method was used to evaluate the reliability of the task, as well as the Intraclass Correlation Coefficient (ICC). The analysis of the test-retest reliability of the scores in the task indicated an excellent clinical relevance for both groups. The hypothesis of equality of the means of the scores in the two applications of the task was accepted for both the ADG and HG, respectively. The task also showed a significant high degree of association with the MEC-35 test (rho = 0.710, p = 0.010) for the ADG. Our results showed that it is possible to use an ADL-based task to assess everyday memory intended for cognitive impairments detection. In the same way, the task could be used to promote cognitive function and prevent dementia.

2 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors review progress over the past decade in observations of large-scale star formation, with a focus on the interface between extragalactic and Galactic studies.
Abstract: We review progress over the past decade in observations of large-scale star formation, with a focus on the interface between extragalactic and Galactic studies. Methods of measuring gas contents and star-formation rates are discussed, and updated prescriptions for calculating star-formation rates are provided. We review relations between star formation and gas on scales ranging from entire galaxies to individual molecular clouds.

2,525 citations

Journal ArticleDOI
TL;DR: SDSS-IV as mentioned in this paper is a project encompassing three major spectroscopic programs: the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and the Time Domain Spectroscopy Survey (TDSS).
Abstract: We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median $z\sim 0.03$). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between $z\sim 0.6$ and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.

1,200 citations

Journal ArticleDOI
Sebastián F. Sánchez1, Robert C. Kennicutt2, A. Gil de Paz3, G. van de Ven4, José M. Vílchez1, Lutz Wisotzki5, C. J. Walcher5, D. Mast1, J. A. L. Aguerri1, J. A. L. Aguerri6, Sergio Albiol-Pérez7, Almudena Alonso-Herrero1, João Alves8, J. Bakos1, J. Bakos6, T. Bartakova9, Joss Bland-Hawthorn10, Alessandro Boselli11, D. J. Bomans12, África Castillo-Morales3, C. Cortijo-Ferrero1, A. de Lorenzo-Cáceres6, A. de Lorenzo-Cáceres1, A. del Olmo1, Ralf-Jürgen Dettmar12, Angeles I. Díaz13, Simon Ellis14, Simon Ellis10, Jesús Falcón-Barroso6, Jesús Falcón-Barroso1, Hector Flores15, Anna Gallazzi16, Begoña García-Lorenzo6, Begoña García-Lorenzo1, R. M. González Delgado1, Nicolas Gruel, Tim Haines17, C. Hao18, Bernd Husemann5, J. Iglesias-Páramo1, Knud Jahnke4, Benjamin D. Johnson19, Bruno Jungwiert20, Bruno Jungwiert21, Veselina Kalinova4, C. Kehrig5, D. Kupko5, Angel R. Lopez-Sanchez14, Angel R. Lopez-Sanchez22, Mariya Lyubenova4, R. A. Marino3, R. A. Marino1, E. Mármol-Queraltó1, E. Mármol-Queraltó3, I. Márquez1, J. Masegosa1, Sharon E. Meidt4, Jairo Méndez-Abreu1, Jairo Méndez-Abreu6, Ana Monreal-Ibero1, C. Montijo1, A. Mourao23, G. Palacios-Navarro7, Polychronis Papaderos24, Anna Pasquali25, Reynier Peletier, Enrique Pérez1, I. Pérez26, Andreas Quirrenbach, M. Relaño26, F. F. Rosales-Ortega1, F. F. Rosales-Ortega13, Martin Roth5, T. Ruiz-Lara26, Patricia Sanchez-Blazquez13, C. Sengupta1, R. Singh4, Vallery Stanishev23, Scott Trager27, Alexandre Vazdekis1, Alexandre Vazdekis6, Kerttu Viironen1, Vivienne Wild28, Stefano Zibetti16, Bodo L. Ziegler8 
TL;DR: The Calar Alto Legacy Integral Field Area (CALIFA) survey as discussed by the authors was designed to provide a first step in this direction by obtaining spatially resolved spectroscopic information of a diameter selected sample of similar to 600 galaxies in the Local Universe.
Abstract: The final product of galaxy evolution through cosmic time is the population of galaxies in the local universe. These galaxies are also those that can be studied in most detail, thus providing a stringent benchmark for our understanding of galaxy evolution. Through the huge success of spectroscopic single-fiber, statistical surveys of the Local Universe in the last decade, it has become clear, however, that an authoritative observational description of galaxies will involve measuring their spatially resolved properties over their full optical extent for a statistically significant sample. We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction. We summarize the survey goals and design, including sample selection and observational strategy. We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of similar to 600 galaxies in the Local Universe (0.005 < z < 0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK integral field unit (IFU), with a hexagonal field-of-view of similar to 1.3 square', with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 angstrom, using two overlapping setups (V500 and V1200), with different resolutions: R similar to 850 and R similar to 1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis: (i) the final datacubes reach a 3 sigma limiting surface brightness depth of similar to 23.0 mag/arcsec(2) for the V500 grating data (similar to 22.8 mag/arcsec(2) for V1200); (ii) about similar to 70% of the covered field-of-view is above this 3 sigma limit; (iii) the data have a blue-to-red relative flux calibration within a few percent in most of the wavelength range; (iv) the absolute flux calibration is accurate within similar to 8% with respect to SDSS; (v) the measured spectral resolution is similar to 85 km s(-1) for V1200 (similar to 150 km s(-1) for V500); (vi) the estimated accuracy of the wavelength calibration is similar to 5 km s(-1) for the V1200 data (similar to 10 km s(-1) for the V500 data); (vii) the aperture matched CALIFA and SDSS spectra are qualitatively and quantitatively similar. Finally, we show that we are able to carry out all measurements indicated above, recovering the properties of the stellar populations, the ionized gas and the kinematics of both components. The associated maps illustrate the spatial variation of these parameters across the field, reemphasizing the redshift dependence of single aperture spectroscopic measurements. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.

1,143 citations

Journal ArticleDOI
TL;DR: MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) as mentioned in this paper employs dithered observations with 17 fiber-bundle integral field units that vary in diameter from 12'' (19 fibers) to 32'' (127 fibers).
Abstract: We present an overview of a new integral field spectroscopic survey called MaNGA (Mapping Nearby Galaxies at Apache Point Observatory), one of three core programs in the fourth-generation Sloan Digital Sky Survey (SDSS-IV) that began on 2014 July 1. MaNGA will investigate the internal kinematic structure and composition of gas and stars in an unprecedented sample of 10,000 nearby galaxies. We summarize essential characteristics of the instrument and survey design in the context of MaNGA's key science goals and present prototype observations to demonstrate MaNGA's scientific potential. MaNGA employs dithered observations with 17 fiber-bundle integral field units that vary in diameter from 12'' (19 fibers) to 32'' (127 fibers). Two dual-channel spectrographs provide simultaneous wavelength coverage over 3600-10300 A at R ~ 2000. With a typical integration time of 3 hr, MaNGA reaches a target r-band signal-to-noise ratio of 4-8 (A–1 per 2'' fiber) at 23 AB mag arcsec–2, which is typical for the outskirts of MaNGA galaxies. Targets are selected with M * 109 M ☉ using SDSS-I redshifts and i-band luminosity to achieve uniform radial coverage in terms of the effective radius, an approximately flat distribution in stellar mass, and a sample spanning a wide range of environments. Analysis of our prototype observations demonstrates MaNGA's ability to probe gas ionization, shed light on recent star formation and quenching, enable dynamical modeling, decompose constituent components, and map the composition of stellar populations. MaNGA's spatially resolved spectra will enable an unprecedented study of the astrophysics of nearby galaxies in the coming 6 yr.

1,104 citations

Journal ArticleDOI
Bela Abolfathi1, D. S. Aguado2, Gabriela Aguilar3, Carlos Allende Prieto2  +361 moreInstitutions (94)
TL;DR: SDSS-IV is the fourth generation of the Sloan Digital Sky Survey and has been in operation since 2014 July. as discussed by the authors describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14).
Abstract: The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.

965 citations