This is the first paper of a series presenting the Spheroids Panchromatic Investigation in Different Environmental Regions (SPIDER). The sample of spheroids consists of 5080 bright (Mr< -20) ...early-type galaxies (ETGs), in the redshift range of 0.05 to 0.095, with optical (griz) photometry and spectroscopy from the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) and near-infrared (YJHK) photometry from the UKIRT Infrared Deep Sky Survey-Large Area Survey (UKIDSS-LAS) (DR4). We describe how homogeneous photometric parameters (galaxy colours and structural parameters) are derived usinggrizYJHKwavebands. We find no systematic steepening of the colour-magnitude relation when probing the baseline fromg-rtog-K, implying that internal colour gradients drive most of the mass-metallicity relation in ETGs. As far as structural parameters are concerned we find that the mean effective radius of ETGs smoothly decreases, by 30 per cent, fromgthroughK, while no significant dependence on waveband is detected for the axial ratio, Sersic index anda4parameters. Furthermore, velocity dispersions are remeasured for all the ETGs usingstarlightand compared to those obtained by SDSS. The velocity dispersions are rederived using a combination of simple stellar population models as templates, hence accounting for the kinematics of different galaxy stellar components. We compare our (2dphot) measurements of total magnitude, effective radius and mean surface brightness with those obtained as part of the SDSS pipeline (photo). Significant differences are found and reported, including comparisons with a third and independent part. A full characterization of the sample completeness in all wavebands is presented, establishing the limits of application of the characteristic parameters presented here for the analysis of the global scaling relations of ETGs. PUBLICATION ABSTRACT
Colonoscopies are usually performed using pharmacological sedation. This process entails certain risks. In the search for alternative methods, some studies have analysed the effect music can have on ...patients during the procedure when used as a complement to sedation. We present a prospective, randomized study in which we assess the anxiolytic action music has when it is administered during a single colonoscopy.
We included 118 patients who were scheduled for ambulatory colonoscopies. They were randomly assigned to the control group (n = 55) and the experimental group (n = 63). We determined their levels of anxiety using the State-Trait Anxiety Inventory Test (STAI) form, which they filled in before and after the examination. Patients listened to music through personal headphones.
The score on the STAI form before the examination was 25.25 +/- 10.49 and 28.16 +/- 11.43 in the control and experimental groups, respectively (P > 0.05). The decrease of the score on the STAI scale after the colonoscopy in the control and experimental groups was 6.27 (95% confidence interval, 3.26-9.28) and 11.35 (95% confidence interval, 8.64-14.05), respectively (P < 0.01).
Listening to music during ambulatory colonoscopies decreases the level of anxiety that is inherent to the process without other anxiolytic methods.
Massive quiescent compact galaxies have been discovered at high redshifts, associated with rapid compaction and cessation of star formation (SF). In this work we set out to quantify the time-scales ...in which SF is quenched in compact galaxies at intermediate redshifts. For this, we select a sample of green valley galaxies within the COSMOS field in the midst of quenching their SF at \(0.5<z<1.0\) that exhibit varying degrees of compactness. Based on the H\(\delta\) absorption line and the 4000 \AA \ break of coadded zCOSMOS spectra for sub-samples of normal-sized and compact galaxies we determine quenching time-scales as a function of compactness. We find that the SF quenching time-scales in green valley compact galaxies are much shorter than in normal-sized ones. In an effort to understand this trend, we use the Illustris simulation to trace the evolution of the SF history, the growth rate of the central super massive black hole (SMBH) {\bf and the AGN-feedback in compact and normal-sized galaxies. We find that the key difference between their SF quenching time-scales is linked to the mode of the AGN-feedback. In the compact galaxies predominates the kinematic-mode, which is highly efficient at quenching the SF by depleting the internal gas. On the normal-sized galaxies, the prevailing thermal-mode injects energy in the circumgalactic gas, impeding the cold gas supply and quenching the SF via the slower strangulation mechanism.} These results are consistent with the violent disk instability and gas-rich mergers scenarios, followed by strong AGN and stellar feedback. Although this kind of event is most expected to occur at \(z=2-3\), we find evidences that the formation of compact quiescent galaxies can occur at \(z<1\).
We present a study focusing on the nature of compact groups (CGs) through the study of their elliptical (E) galaxies. Parameters describing the internal dynamics and the stellar populations of the ...galaxies are compared with their counterparts in other environments. Our sample has24 bright E galaxies located in the core of Hickson CGs and 11 bright 'bona fide' Es, located in the field or very loose groups. Their spectra were obtained with the 2.1 m Telescope at KPNO and have a 4.1 Aa resolution over the wavelength range 3500-7000 Aa. We have found that, from the dynamical point of view, E galaxies in CGs are essentially similar to those in dense clusters. Moreover, the stellar populations of Es in CGs seem to be older and less metal rich than those in the field, behaviour which has also been observed by Rose et al. (1994).
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