IWDMS2018 - International Workshop on Dark Matter and Stars

Session

Poster session

11 Dec 2018, 14:00

Anfiteatro Abreu Faro (Center for Astrophysics and Gravitation, Instituto Superior Técnico, University of Lisbon)

37. 21-cm observations and warm dark matter models

Anton Rudakovskyi

The recent report of 21-cm absorption signal by EDGES experiment has raised considerable interest in the dark matter (DM) community. Taking the reported EDGES result at face value, a number of forthcoming papers constrained masses of DM particles and their interaction strengths with Standard Model particles.

However, the connection between the formation of structures and 21-cm EDGES...

19. 3.5 keV line in the Galactic bulge region

Denys Savchenko (BITP)

The 3.5 keV line, discovered in early 2014 in the spectra of different cosmic objects, draws large attention as being the dark matter signal candidate. Much effort was performed since then to determine it's nature. The one conclusion to point out is that the dark matter signal is by now the only explanation consistent with all the observational data available.
We are presenting the detection...

42. Axion-Plasmon Polaritons in Strongly Magnetized Plasmas

Hugo Terças (IPFN, Instituto Superior Técnico)

Axions are hypothetical particles related to the violation of the charge-parity symmetry within the strong sector of the standard model, being one of the most prone candidates for dark matter. Multiple attempts to prove their existence are currently performed in different physical systems. Here, we predict that axions may couple to the electrostatic (Langmuir) modes of a strongly magnetized...

36. Machine learning technique for morphological classification of galaxies

Dr Daria Dobrycheeva (Main Astronomical Observatory of the NAS of Ukraine)

We checked classifiers as Naive Bayes, Random Forest, and Support Vector Classifier on sample of galaxies from SDSS DR9 (N=60561, 0.02<z<0.06). We used the absolute magnitudes Mu, Mg, Mr, Mi, and Mz, all the color indices, and inverse concentration indexes R50/R90 to the center as the attributes of galaxy. To define an accuracy of the mentioned above classifiers we applied the 5-folds...

41. Partial ionization and stellar rotation: a seismic connection in F-type stars

Ana Brito (IST/CENTRA)

F-type stars are very diverse concerning magnetic and rotational properties. As it is well know, in these stars magnetism and rotation are intimately linked. Understanding how these macroscopic observable properties relate to the physics of the stellar interiors is a challenging exercise.

We studied the relation between the star's rotation period and partial ionization processes occurring in...

35. Rotating clumps of scalar field dark matter

Miguel Ferreira (CENTRA, Instituto Superior Técnico)

Low-energy, self-gravitating solutions of a scalar field coupled to gravity, described by the Schrodinger-Poisson system, are good candidates for realistic astrophysical structures, being particularly suited to describe dark matter halos. In this work we study the scenario in which one of these structures is gravitationally perturbed by a point-like mass. We analyse the effects that the body...

17. The shadow of dark matter as a shadow of sting theory

Andrii Dashko (Taras Shevchenko National University of Kyiv )

We point out that the Kalb-Ramond field of string theory can help to generate a $U_{Y}(1)$ portal to dark matter. This entails the possibility that the $U_{Y}(1)$ gauge field is related to a fundamental vector field for open string interactions. The $U_{Y}(1)$ portal also implies dipole and fluorescent dark matter couplings of the form initially suggested by Profumo and Sigurdson [1], and...