New blackhole mass measuring method

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A new method for measuring black hole masses using molecular gas kinematics has been proposed, which could significantly enhance our understanding of supermassive black holes and their relationship with galaxy evolution. This technique utilizes the Doppler shift of carbon monoxide emissions to analyze the rotation of gas clouds around black holes, allowing for accurate mass estimates. In the study of the early-type galaxy NGC4526, researchers determined a central dark object mass of approximately 4.5 x 10^8 solar masses. The method promises to enable mass measurements in hundreds of galaxies within the local universe, far exceeding the capabilities of current techniques. This advancement could lead to a deeper insight into the co-evolution of galaxies and their central black holes.
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Mordred said:
Thought this article may spark some interest if it works out we may gain a better understand of BH's.
http://www.sciencedaily.com/releases/2013/01/130130132324.htm

Here is an earlier article by some of the same authors that might be interesting as background to the one you mention:
http://arxiv.org/abs/1102.4877

Using the radio frequency emitted by carbon monoxide molecules to measure rotation---the swirling of gas cloud around a central mass---the doppler shift of the gas coming towards versus the gas going from. It's an interesting business. I hope we can sometime get an online link to the Nature article. I don't have one.

Timothy A. Davis, Martin Bureau, Michele Cappellari, Marc Sarzi, Leo Blitz. A black-hole mass measurement from molecular gas kinematics in NGC4526. Nature, 2013

Here's another link to comment on the article:
http://arstechnica.com/science/2013/01/better-black-hole-mass-estimates-in-hours/

Here's a link to supplementary material:
http://www.nature.com/nature/journal/vaop/ncurrent/extref/nature11819-s1.pdf

Here's the abstract of the article just published in Nature (but not the full article):
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11819.html
==quote==
A black-hole mass measurement from molecular gas kinematics in NGC4526
...
...
The masses of the supermassive black holes found in galaxy bulges are correlated with a multitude of galaxy properties1, 2, leading to suggestions that galaxies and black holes may evolve together3. The number of reliably measured black-hole masses is small, and the number of methods for measuring them is limited4, holding back attempts to understand this co-evolution. Directly measuring black-hole masses is currently possible with stellar kinematics (in early-type galaxies), ionized-gas kinematics (in some spiral and early-type galaxies5, 6, 7) and in rare objects that have central maser emission8. Here we report that by modelling the effect of a black hole on the kinematics of molecular gas it is possible to fit interferometric observations of CO emission and thereby accurately estimate black-hole masses. We study the dynamics of the gas in the early-type galaxy NGC 4526, and obtain a best fit that requires the presence of a central dark object of 4.5+4.2-3.1  × 108 solar masses (3σ confidence limit). With the next-generation millimetre-wavelength interferometers these observations could be reproduced in galaxies out to 75 megaparsecs in less than 5 hours of observing time. The use of molecular gas as a kinematic tracer should thus allow one to estimate black-hole masses in hundreds of galaxies in the local Universe, many more than are accessible with current techniques.
==endquote==
 
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Awesome thanks for the other links, Its always nice getting the non pop media articles lol
 
Preprint just posted half an hour ago! Now we have free access, not limited to subscribers to Nature.
http://arxiv.org/abs/1301.7184
A black-hole mass measurement from molecular gas kinematics in NGC4526
Timothy A. Davis, Martin Bureau, Michele Cappellari, Marc Sarzi, Leo Blitz
(Submitted on 30 Jan 2013)
The masses of the supermassive black-holes found in galaxy bulges are correlated with a multitude of galaxy properties, leading to suggestions that galaxies and black-holes may evolve together. The number of reliably measured black-hole masses is small, and the number of methods for measuring them is limited, holding back attempts to understand this co-evolution. Directly measuring black-hole masses is currently possible with stellar kinematics (in early-type galaxies), ionised-gas kinematics (in some spiral and early-type galaxies) and in rare objects which have central maser emission. Here we report that by modelling the effect of a black-hole on the kinematics of molecular gas it is possible to fit interferometric observations of CO emission and thereby accurately estimate black hole masses. We study the dynamics of the gas in the early-type galaxy NGC4526, and obtain a best fit which requires the presence of a central dark-object of 4.5(+4.2-3.0)x10^8 Msun (3 sigma confidence limit). With next generation mm-interferometers (e.g. ALMA) these observations could be reproduced in galaxies out to 75 megaparsecs in less the 5 hours of observing time. The use of molecular gas as a kinematic tracer should thus allow one to estimate black-hole masses in hundreds of galaxies in the local universe, many more than accessible with current techniques.
Comments: To appear in Nature online on 30/01/2013. 3 Pages, 2 Figures (plus two pages of supplementary information)
 
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
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