Observational rotation curves and density profiles versus the Thomas-Fermi galaxy structure theory

The Thomas-Fermi approach to galaxy structure determines self-consistently the gravitational potential of the fermionic warm dark matter (WDM) given its distribution function f(E). This framework is appropriate for macroscopic quantum systems as neutron stars, white dwarfs and WDM galaxies. Compact dwarf galaxies are near the quantum degenerate regime, while large galaxies are in the classical Boltzmann regime. We derive analytic scaling relations for the main galaxy magnitudes: halo radius rh, mass Mh and phase-space density. Small deviations from the exact scaling show up for compact dwarfs due to quantum macroscopic effects. We contrast the theoretical curves for the circular galaxy velocities vc(r) and density profiles \u3c1(r) with those obtained from observations using the empirical Burkert profile. Results are independent of any WDM particle physics model, they only follow from the gravitational interaction of the WDM particles and their fermionic nature. The theoretical rotation curves and density profiles reproduce very well the observational curves for r 72 rh obtained from 10 different and independent sets of data for galaxy masses from 5 7 109 to 5 7 1011M 99. Our normalized theoretical circular velocities and normalized density profiles turn to be universal functions of r/rh for all galaxies. In addition, they agree extremely well with the observational curves described by the Burkert profile for r 72 2 rh. These results showthat the Thomas-Fermi approach correctly describes the galaxy structures

Dark Matter Universal Properties in Galaxies

In the past years a wealth of observations has unraveled the structural properties of dark and luminous mass distribution in galaxies, a benchmark for understanding dark matter and the process of galaxy formation. The study of the kinematics of over thousand spirals has evidenced a dark-luminous matter coupling and the presence of a series of scaling laws, pictured by the Universal Rotation Curve paradigm, an intriguing observational scenario not easily explained by present theories of galaxy formation.Comment: Proceedings of the VI International Workshop on the Dark side of the Universe. June 01-06, 2010. Le\'on, M\'exic

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

The dark matter distribution in the spiral NGC 3198 out to 0.22 Rvir

Aims. We use recent very extended HI kinematics (out to 48 kpc) along with previous H\u3b1 kinematics of the spiral galaxy NGC 3198 in order to derive its distribution of dark matter (DM). Methods. First, we used a chi-square method to model the rotation curve (RC) of this galaxy in terms of different profiles of its DM distribution: the universal RC (URC) mass model (stellar disk + Burkert halo + gaseous disk), the NFW mass model (stellar disk + NFW halo + gaseous disk) and the baryon \u39bCDM mass model (stellar disk + NFW halo modified by baryonic physics + gaseous disk). Second, to derive the DM halo density distribution, we applied a new method that does not require a global and often uncertain mass modelling. Results. While according to the standard method, both URC and NFW mass models can account for the RC, the new method instead leads to a density profile that is sharply disagrees with the dark halo density distribution predicted within the Lambda cold dark matter (\u39bCDM) scenario. We find that the effects of baryonic physics modify the original \u39bCDM halo densities in such a way that the resulting profile is more compatible with the DM density of NGC 3198 derived using our new method. However, at large distances, r ~ 25 kpc, also this modified baryon \u39bCDM halo profile appears to create a tension with the derived DM halo density