Some Regularities in the Missing Mass Problem

Symposium - International Astronomical Union ◽

10.1017/s0074180900150089 ◽

1987 ◽

Vol 117 ◽

pp. 136-136

Author(s):

S. Casertano ◽

J. N. Bahcall

Keyword(s):

Dark Matter ◽

Rotation Curve ◽

Full Description ◽

Mass Model ◽

Missing Mass ◽

Mass Problem ◽

Available Information ◽

Optical Radius

We discuss available information on the distribution of luminous and dark matter in eight galaxies. The galaxies have been chosen according to the following criteria: 1) existence of a good rotation curve, extending well beyond the optical radius; 2) a mass model has been published; 3) valuable constraints can be put on the amount of dark matter inside the optical radius. A full description of the data and reduction procedures is in Bahcall and Casertano (1985).

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The dynamics of galaxies and the 'missing mass' problem

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1980.0175 ◽

1980 ◽

Vol 296 (1419) ◽

pp. 313-318 ◽

Cited By ~ 8

Keyword(s):

Dark Matter ◽

Rotation Curve ◽

Simple Theory ◽

Missing Mass ◽

Mass Problem ◽

The Galaxy ◽

Dynamics Of Galaxies ◽

New Evidence

I review the observational situation concerning the existence of dark matter in the outer parts of galaxies. Observation now leaves little doubt of its presence, and both observation and simple theory suggest that the dark matter is probably bound to galaxies, and furthermore is present around both spirals and ellipticals. New evidence concerning the rotation curve of the Galaxy shows that the distribution of the halo stuff in our own system is roughly spherical, as seems natural from existing dynamical data on the nature of the halo material.

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DARK GEOMETRY

International Journal of Modern Physics D ◽

10.1142/s0218271804006322 ◽

2004 ◽

Vol 13 (10) ◽

pp. 2275-2279 ◽

Cited By ~ 31

Author(s):

J. A. R. CEMBRANOS ◽

A. DOBADO ◽

A. L. MAROTO

Keyword(s):

Dark Matter ◽

Extra Dimensions ◽

Degrees Of Freedom ◽

Planck Scale ◽

Point Of View ◽

Missing Mass ◽

Brane Worlds ◽

Mass Problem ◽

Extra Space ◽

The Universe

Extra-dimensional theories contain additional degrees of freedom related to the geometry of the extra space which can be interpreted as new particles. Such theories allow to reformulate most of the fundamental problems of physics from a completely different point of view. In this essay, we concentrate on the brane fluctuations which are present in brane-worlds, and how such oscillations of the own space–time geometry along curved extra dimensions can help to resolve the Universe missing mass problem. The energy scales involved in these models are low compared to the Planck scale, and this means that some of the brane fluctuations distinctive signals could be detected in future colliders and in direct or indirect dark matter searches.

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GHASP: an H α kinematical survey of spiral galaxies – XIII. Distribution of luminous and dark matter in spiral and irregular nearby galaxies using H α and H i rotation curves and WISE photometry

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2678 ◽

2019 ◽

Vol 490 (3) ◽

pp. 2977-3024 ◽

Cited By ~ 2

Author(s):

M Korsaga ◽

B Epinat ◽

P Amram ◽

C Carignan ◽

P Adamczyk ◽

...

Keyword(s):

Dark Matter ◽

Model Parameters ◽

Data Sets ◽

Mass Model ◽

Rotation Curves ◽

Fitting Procedures ◽

Nearby Galaxies ◽

Halo Masses ◽

Gas Component ◽

Optical Radius

Abstract We present the mass models of 31 spiral and irregular nearby galaxies obtained using hybrid rotation curves (RCs) combining high-resolution GHASP Fabry–Perot H α RCs and extended WHISP H i ones together with 3.4 $\mu$m WISE photometry. The aim is to compare the dark matter (DM) halo properties within the optical radius using only H α RCs with the effect of including and excluding the mass contribution of the neutral gas component, and when using H i or hybrid RCs. Pseudo-isothermal (ISO) core and Navarro–Frenk–White (NFW) cuspy DM halo profiles are used with various fiducial fitting procedures. Mass models using H α RCs including or excluding the H i gas component provide compatible disc M/L. The correlations between DM halo and baryon parameters do not strongly depend on the RC. Clearly, the differences between the fitting procedures are larger than between the different data sets. Hybrid and H i RCs lead to higher M/L values for both ISO and NFW best-fitting models but lower central densities for ISO haloes and higher concentration for NFW haloes than when using H α RCs only. The agreement with the mass model parameters deduced using hybrid RCs, considered as a reference, is better for H i than for H α RCs. ISO density profiles better fit the RCs than the NFW ones, especially when using H α or hybrid RCs. Halo masses at the optical radius determined using the various data sets are compatible even if they tend to be overestimated with H α RCs. Hybrid RCs are thus ideal to study the mass distribution within the optical radius.

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The ‘Missing Mass Problem’ in Astronomy and the Need for a Modified Law of Gravity

Zeitschrift für Naturforschung A ◽

10.5560/zna.2014-0003 ◽

2014 ◽

Vol 69 (3-4) ◽

pp. 173-187 ◽

Cited By ~ 7

Author(s):

Sascha Trippe

Keyword(s):

Dark Matter ◽

Stellar Dynamics ◽

Stellar Systems ◽

Gravitational Acceleration ◽

Missing Mass ◽

Astronomical Observations ◽

Groups Of Galaxies ◽

Mass Problem ◽

Multiple Observations ◽

Law Of Gravity

Since the 1930s, astronomical observations have accumulated evidence that our understanding of the dynamics of galaxies and groups of galaxies is grossly incomplete: assuming the validity of Newton’s law of gravity on astronomical scales, the observed mass (stored in stars and interstellar gas) of stellar systems can account only for roughly 10% of the dynamical (gravitating) mass required to explain the high velocities of stars in those systems. The standard approach to this ‘missing mass problem’ has been the postulate of ‘dark matter’, meaning an additional, electromagnetically dark, matter component that provides the missing mass. However, direct observational evidence for dark matter has not been found to date. More importantly, astronomical observations obtained during the last decade indicate that dark matter cannot explain the kinematics of galaxies. Multiple observations show that the discrepancy between observed and dynamical mass is a function of gravitational acceleration (or field strength) but not of other parameters (size, rotation speed, etc.) of a galaxy; the mass discrepancy appears below a characteristic and universal acceleration aM = (1:1±0:1) · 10-10 ms-2 (Milgrom’s constant). Consequently, the idea of a modified law of gravity, specifically the ansatz of modified Newtonian dynamics (MOND), is becoming increasingly important in astrophysics. MOND has successfully predicted various important empirical relations of galaxy dynamics, including the famous Tully-Fisher and Faber-Jackson relations. MOND is found to be consistent with stellar dynamics from binary stars to clusters of galaxies, thus covering stellar systems spanning eight orders of magnitude in size and 14 orders of magnitude in mass. These developments have the potential to initiate a paradigm shift from dark matter to a modified law of gravity as the physical mechanism behind the missing mass problem.

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Dark matter candidates in a type-II radiative neutrino mass model

Journal of High Energy Physics ◽

10.1007/jhep06(2021)072 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Roberto A. Lineros ◽

Mathias Pierre

Keyword(s):

Dark Matter ◽

Neutral Particle ◽

Matter Density ◽

Indirect Detection ◽

Dark Matter Candidate ◽

Neutrino Masses ◽

Type Ii ◽

Mass Model ◽

Direct And Indirect Detection

Abstract We explore the connection between Dark Matter and neutrinos in a model inspired by radiative Type-II seessaw and scotogenic scenarios. In our model, we introduce new electroweakly charged states (scalars and a vector-like fermion) and impose a discrete ℤ2 symmetry. Neutrino masses are generated at the loop level and the lightest ℤ2-odd neutral particle is stable and it can play the role of a Dark Matter candidate. We perform a numerical analysis of the model showing that neutrino masses and flavour structure can be reproduced in addition to the correct dark matter density, with viable DM masses from 700 GeV to 30 TeV. We explore direct and indirect detection signatures and show interesting detection prospects by CTA, Darwin and KM3Net and highlight the complementarity between these observables.

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A Review of Basic Energy Reconstruction Techniques in Liquid Xenon and Argon Detectors for Dark Matter and Neutrino Physics Using NEST

Instruments ◽

10.3390/instruments5010013 ◽

2021 ◽

Vol 5 (1) ◽

pp. 13

Author(s):

Matthew Szydagis ◽

Grant A. Block ◽

Collin Farquhar ◽

Alexander J. Flesher ◽

Ekaterina S. Kozlova ◽

...

Keyword(s):

Dark Matter ◽

Neutrino Physics ◽

Electric Fields ◽

Direct Detection ◽

Profile Likelihood ◽

Liquid Argon ◽

Energy Scale ◽

Liquid Xenon ◽

Nuclear Recoils ◽

Available Information

Detectors based upon the noble elements, especially liquid xenon as well as liquid argon, as both single- and dual-phase types, require reconstruction of the energies of interacting particles, both in the field of direct detection of dark matter (weakly interacting massive particles WIMPs, axions, etc.) and in neutrino physics. Experimentalists, as well as theorists who reanalyze/reinterpret experimental data, have used a few different techniques over the past few decades. In this paper, we review techniques based on solely the primary scintillation channel, the ionization or secondary channel available at non-zero drift electric fields, and combined techniques that include a simple linear combination and weighted averages, with a brief discussion of the application of profile likelihood, maximum likelihood, and machine learning. Comparing results for electron recoils (beta and gamma interactions) and nuclear recoils (primarily from neutrons) from the Noble Element Simulation Technique (NEST) simulation to available data, we confirm that combining all available information generates higher-precision means, lower widths (energy resolution), and more symmetric shapes (approximately Gaussian) especially at keV-scale energies, with the symmetry even greater when thresholding is addressed. Near thresholds, bias from upward fluctuations matters. For MeV-GeV scales, if only one channel is utilized, an ionization-only-based energy scale outperforms scintillation; channel combination remains beneficial. We discuss here what major collaborations use.

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The Dark Matter Halo Density Profile, Spiral Arm Morphology, and Supermassive Black Hole Mass of M33

ISRN Astronomy and Astrophysics ◽

10.5402/2011/725697 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Marc S. Seigar

Keyword(s):

Black Hole ◽

Dark Matter ◽

Density Profile ◽

Pitch Angle ◽

Rotation Curve ◽

Dark Matter Halo ◽

Black Hole Mass ◽

Supermassive Black Hole ◽

Virial Mass ◽

Spiral Arm

We investigate the dark matter halo density profile of M33. We find that the HI rotation curve of M33 is best described by an NFW dark matter halo density profile model, with a halo concentration of and a virial mass of . We go on to use the NFW concentration of M33, along with the values derived for other galaxies (as found in the literature), to show that correlates with both spiral arm pitch angle and supermassive black hole mass.

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