Mass Models for Low Surface Brightness Galaxies with High Resolution Optical Velocity Fields

Rachel Kuzio de Naray; Stacy S. McGaugh; W. J. G. de Blok

doi:10.1086/527543

Home/Archive/arXiv

arXiv · 0712.0860

Mass Models for Low Surface Brightness Galaxies with High Resolution Optical Velocity Fields

Rachel Kuzio de Naray·Stacy S. McGaugh·W. J. G. de Blok

View original source ↗Read source document ↗Export metadata ↓

Abstract

We present high-resolution optical velocity fields from DensePak integral field spectroscopy, along with derived rotation curves, for a sample of low surface brightness galaxies. In the limit of no baryons, we fit the NFW and pseudoisothermal halo models to the data and find the rotation curve shapes and halo central densities to be better described by the isothermal halo. For those galaxies with photometry, we present halo fits for three assumptions of the stellar mass-to-light ratio. We find that the velocity contribution from the baryons is significant enough in the maximum disk case that maximum disk and the NFW halo are mutually exclusive. We find a substantial cusp mass excess at the centers of the galaxies, with at least two times more mass expected in the cuspy CDM halo than is allowed by the data. We also find that to reconcile the data with LCDM, ~20 km/s noncircular motions are needed and/or the power spectrum has a lower amplitude on the scales we probe.

Explore related subjects

astro-ph

Keep this discovery

BibTeX RIS

Rachel Kuzio de Naray, Stacy S. McGaugh, W. J. G. de Blok. 2007-12-06. Mass Models for Low Surface Brightness Galaxies with High Resolution Optical Velocity Fields. https://doi.org/10.1086/527543

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2018

Putting The Together A Cyclical Baryonic Universe

There are multiple examples of gravitational losses in neutron stars and black holes. Protons and neutrons have been found to have enormous repulsive pressures that highly squeezed collapsing matter cannot overcome. The case against singularities follows. Galactic black hole gravitational losses can supply the missing dark energy. With highly squeezed nucleons, the big bang could begin as a hot core and a cold dark matter shell. The 21 cm. radiation data has identified baryon sized particles as cold dark matter. Highly squeezed nucleons will not decompose to produce antimatter. The flatness of the Universe is due to a baryonic bounce. The highly correlated galaxies originated from primordial black holes capturing hot core gasses.There is evidence that galaxies have not grown nor merged significantly since formation.

astro-ph↗

arXiv2018

Direct observation of high-speed plasma outflows produced by magnetic reconnection in solar impulsive events

Spectroscopic observations of a solar limb flare recorded by SUMER on SOHO reveal, for the first time, hot fast magnetic reconnection outflows in the corona. As the reconnection site rises across the SUMER spectrometer slit, significant blue- and red-shift signatures are observed in sequence in the Fe XIX line, reflecting upflows and downflows of hot plasma jets, respectively. With the projection effect corrected, the measured outflow speed is between 900-3500 km/s, consistent with theoretical predictions of the Alfvenic outflows in magnetic reconnection region in solar impulsive events. Based on theoretic models, the magnetic field strength near the reconnection region is estimated to be 19-37 Gauss.

astro-ph↗

arXiv2018

Multiwavelength evidence of the physical processes in radio jets

Over the last few years, high-quality X-ray imaging and spectroscopic data from Chandra and XMM-Newton have added greatly to the understanding of the physics of radio jets. Here we describe the current state of knowledge with an emphasis on the underlying physics used to interpret multiwavelength data in terms of physical parameters.

astro-ph↗