Context. Observations of the Galactic bulge suggest that the disk formed through secular evolution rather than gas dissipation and/or mergers, as previously believed. This would imply very similar chemistry in the disk and bulge. Some elements, such as the α-elements, are well studied in the bulge, but others like the neutron-capture elements are much less well explored. Stellar mass and metallicity are factors that affect the neutron-capture process. Due to this, the enrichment of the ISM and the abundance of neutron-capture elements vary with time, making them suitable probes for Galactic chemical evolution. Aims. In this work, we make a differential comparison of neutron-capture element abundances determined in the local disk(s) and the bulge, focusing on minimising possible systematic effects in the analysis, with the aim of finding possible differences/similarities between the populations. Methods. Abundances are determined for Zr, La, Ce, and Eu in 45 bulge giants and 291 local disk giants, from high-resolution optical spectra. The abundances are determined by fitting synthetic spectra using the SME-code. The disk sample is separated into thin- and thick-disk components using a combination of abundances and kinematics. Results. We find flat Zr, La, and Ce trends in the bulge, with a ~0.1 dex higher La abundance compared with the disk, possibly indicating a higher s-process contribution for La in the bulge. [Eu/Fe] decreases with increasing [Fe/H], with a plateau at around [Fe/H] ~−0.4, pointing at similar enrichment to α-elements in all populations. Conclusions. We find that the r-process dominated the neutron-capture production at early times both in the disks and bulge. Further, [La/Eu] ratios for the bulge are systematically higher than for the thick disk, pointing to either a) a different amount of SN II or b) a different contribution of the s-process in the two populations. Considering [(La+Ce)/Zr], the bulge and the thick disk follow each other closely, suggesting a similar ratio of high-to-low-mass asymptotic giant branch stars.

The cosmic origin of fluorine is still not well constrained. Several nucleosynthetic channels at different phases of stellar evolution have been suggested, but these must be constrained by observations. For this, the fluorine abundance trend with metallicity spanning a wide range is required. Our aim is to determine stellar abundances of fluorine for −1.1 < [Fe/H] < +0.4. We determine the abundances from HF lines in infrared K-band spectra (∼ 2.3 µm) of cool giants, observed with the IGRINS and Phoenix high-resolution spectrographs. We derive accurate stellar parameters for all our observed K giants, which is important since the HF lines are very temperature sensitive. We find that [F/Fe] is flat as a function of metallicity at [F/Fe]∼ 0, but increases as the metallicity increases. The fluorine slope shows a clear secondary behavior in this metallicity range. We also find that the [F/Ce] ratio is relatively flat for −0.6 < [Fe/H] < 0, and that for two metal-poor ([Fe/H] < −0.8), s-process element enhanced giants, we do not detect an elevated fluorine abundance. We interpret all these observational constraints to indicate that several major processes are at play for the cosmic budget of fluorine over time; from those in massive stars at low metallicities, through the asymptotic giant branch-star contribution at −0.6 < [Fe/H] < 0, to processes with increasing yields with metallicity at super-solar metallicities. The origins of the latter, and whether or not Wolf-Rayet stars and/or novae could contribute at super-solar metallicities, is currently not known. To quantify these observational results, theoretical modelling is required. More observations in the metal-poor region are required to clarify the processes there.

We study the chemical evolution of Zr, La, Ce and Eu in the Milky Way discs and bulge by means of chemical evolution models compared with spectroscopic data. We consider detailed chemical evolution models for the Galactic thick disc, thin disc and bulge, which have been already tested to reproduce the observed [α/Fe] vs. [Fe/H] diagrams and metallicity distribution functions for the three different components, and we apply them to follow the evolution of neutron capture elements. In the [Eu/Fe] vs. [Fe/H] diagram, we observe and predict three distinct sequences corresponding to the thick disc, thin disc and bulge, similarly to what happens for the α-elements. We can nicely reproduce the three sequences by assuming different timescales of formation and star formation efficiencies for the three different components, with the thin disc forming on a longer timescale of formation with respect to the thick disc and bulge. On the other hand, in the [X/Fe] vs. [Fe/H] diagrams for Zr, La and Ce, the three populations are mixed and also from the model point of view there is an overlapping between the predictions for the different Galactic components, but the observed behaviour can be also reproduced by assuming different star formation histories in the three components. In conclusions, it is straightforward to see how different star formation histories can lead to different abundance patterns and also looking at the abundance patterns of neutron capture elements can help in constraining the history of formation and evolution of the major Galactic components.

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This is a descriptive study of the medical responses to the bombings by terrorists in Madrid on 11 March 2004. The nature of the event, the human damage, and the responses are described. It describes the: (1) nature and operations associated with the alarm; (2) assignment of responding units and personnel; (3) establishment and operations of casualty collection points; (4) medical transport and distribution of injured victims; (5) prioritization and command; (6) hospital care; (7) psychosocial care; (8) identification of the dead; and (9) police investigation and actions. Each of these descriptions is discussed in terms of what currently is known and the implications for future planning, preparedness, and response.