Related papers: Is Holmberg-II beyond MOND theory?
MOND predicts that the asymptotic gravitational potential of an isolated, bounded (baryonic) mass, M, is phi(r)=(MGa0)^{1/2}ln(r); a0 is the MOND constant. Relativistic MOND theories predict that the lensing effects of M are dictated by…
A sample of 197 X-ray emitting clusters of galaxies is considered in the context of Milgrom's modified Newtonian dynamics (MOND). It is shown that the gas mass, extrapolated via an assumed $\beta$ model to a fixed radius of 3 Mpc, is…
We examine the dependence between hydrogen total mass $M_{HI}$ and rotation speed $V_{rot}$, optical size $D_{25}$ or disc radial scale $R_0$ for two samples of late-type galaxies: a) isolated galaxy (AMIGA sample), and b) the edge-on…
The High Resolution Echelle Spectrometer on the Keck I telescope has been used to measure nine radial velocities having a median precision of 2 km/s for seven red giants belonging to the isolated dwarf spheroidal galaxy Andromeda II. We…
(Abridged) We present evidence that the HII regions of high luminosity in disk galaxies may be density bounded, so that a significant fraction of the ionizing photons emitted by their exciting OB stars escape from the regions. The key piece…
We present new maps of emission-line flux distributions and kinematics in both ionized (traced by HI and [FeII] lines) and molecular (H2) gas of the inner 0.7x0.7kpc2 of the galaxy NGC4303, with a spatial resolution 40-80pc and velocity…
Among the initial results from Kepler were two striking lightcurves, for KOI 74 and KOI 81, in which the relative depths of the primary and secondary eclipses showed that the more compact, less luminous object was hotter than its stellar…
MOdified Newtonian Dynamics (MOND) is evolving from an empirical to a decent theory respecting fundamental physics after Bekenstein (2004) showed that lensing and Hubble expansion can be modeled rigourously in a Modified Relativity. The…
We present a study of the abundances and physical conditions in the interstellar gas toward the heavily reddened star HD 192639 [E_(B-V) = 0.64], based on analysis of FUSE and HST/STIS spectra covering the range from 912 to 1361 A. This…
We present 21cm HI line observations of the blue compact dwarf galaxy NGC1705. Previous optical observations show a strong outflow powered by an ongoing starburst dominating the HII morphology and kinematics. In contrast, most of the HI…
Neutral hydrogen VLA D-array observations of the dwarf irregular galaxy HoII, a prototype galaxy for studies of shell formation and self-propagating star formation, are presented. The large-scale HI morphology is reminiscent of ram pressure…
High-resolution spectroscopic measurements of blue horizontal-branch stars in six metal-poor globular clusters -- M3, M13, M15, M68, M92, and NGC 288 -- reveal remarkable variations in photospheric composition and rotation velocity as a…
The presence of dark matter, though well established by indirect evidence, is yet to be observed directly. Various dark matter detection experiments running for several years have yielded no positive results. In view of these negative…
I consider the growth of inhomogeneities in a low-density baryonic, vacuum energy-dominated universe in the context of modified Newtonian dynamics (MOND). I first write down a two-field Langrangian-based theory of MOND (non-relativistic),…
The dynamical stability of disk galaxies is sensitive to whether their anomalous rotation curves are caused by dark matter halos or Milgromian Dynamics (MOND). We investigate this by setting up a MOND model of M33. We first simulate it in…
We have observed the central region of the nearby starburst galaxy NGC 253 with the Kyoto Tridimensional Spectrograph II (Kyoto3DII) Fabry-Perot mode in order to investigate the properties of its galactic wind. Since this galaxy has a large…
We present the results of spectrophotometric observations of the old nova RR Pic performed in two spectral ranges, one centered in the Ha line and other covering Hb and Hg spectral lines. From the Hb radial velocity study we found a primary…
Milgrom has proposed that the appearance of discrepancies between the Newtonian dynamical mass and the directly observable mass in astronomical systems could be due to a breakdown of Newtonian dynamics in the limit of low accelerations…
We present VLA observations of the distribution and kinematics of the HI gas in the classical ring galaxy VIIZw466 and its immediate surroundings. The HI gas corresponding to the bright optical star forming ring exhibits the typical profile…
With the release of Gaia DR3, we extend the comparison between dynamical models for the Milky Way rotation curve initiated in the previous work. Utilising astrometric and spectro-photometric data for 719143 young disc stars within $|z|<1$…