Searcharxiv⌕ Search

arXiv subjects

Paola Alvarez-Hurtado

Publications and source records attributed to Paola Alvarez-Hurtado.

2 recordsLinked to original sources

Chemical evolution history of MaNGA galaxies

We show the results of a study using the spectral synthesis technique study for the full MaNGA sample showing their Chemical Enrichment History (ChEH) as well as the evolution of the stellar mass-metallicity relation (MZR) over cosmic time. We find that the more massive galaxies became enriched first and the lower mass galaxies did so later, producing a change in the MZR which becomes shallower in time. Separating the sample into morphology and star-forming status bins some particularly interesting results appear: The mass dependency of the MZR becomes less relevant for later morphological types, to the extent that it inverts for Sd/Irr galaxies, suggesting that morphology is at least as important a factor as mass in chemical evolution. The MZR for the full sample shows a flattening at the high-mass end and another at the low-mass range, but the former only appears for retired galaxies while the latter only appears for star-forming galaxies. We also find that the average metallicity gradient is currently negative for all mass bins but for low mass galaxies it was inverted at some point in the past, before which all galaxies had a positive gradient. We also compare how diverse the ChEHs are in the different bins considered as well as what primarily drives the diversity: How much galaxies become enriched or how quickly they do so.

astro-ph.GA↗

Correlation of high energy neutrinos and gamma rays on the direction of Fermi Bubbles

We study the spatial correlation of astrophysical neutrinos detected by IceCube with the geometry of the two large globular structures located in the center of our Galaxy, known as Fermi Bubbles (FB). Using the Fermi-LAT data collected during 8 years and the upper limits derived by the High Altitude Water Cherenkov (HAWC) gamma-ray observatory, we use a hybrid (lepto-hadronic) model to investigate a possible correlation with the high-energy neutrinos in the direction of the Fermi Bubbles. We find that these events are possibly not associated with the Northern Bubble but do not dismiss a possible correlation with the Southern globular structure. We expect in the coming years to improve the gamma-ray observations through the Cerenkov Telescope Array (CTA) and the Southern Gamma-Ray Survey Observatory (SGSO) observatories to test a possible hadronic emission with the Southern Bubble.

astro-ph.HE↗