Shedding light on the power of M 82's superwinds

Jan 19, 2013
Shedding light on the power of M 82's superwinds
Figure 1: Sketches of possible ionization sources of M 82's cap (Credit: NAOJ) Left: Ultraviolet photons from massive stars in the M 82 starburst region. Right: Ultraviolet photons from shockwaves caused by the collision between M 82's galactic winds and gas clouds.

(Phys.org)—An international team of astronomers, led by Dr. Kazuya Matsubayshi (Kyoto University), has discovered that outflows of gas from starburst galaxy M 82 collide with a "cap" of gas clouds 40,000 light years away from the galactic disk. Shockwaves from M 82's central starburst region are the most likely source of the bright clouds within the cap. The large light-gathering power of Subaru Telescope's 8.2-m mirror and its ability to produce highly detailed images enabled the researchers to make these findings, which provide important clues about the wind's power.

The central regions of starburst galaxies are sites of immense . They give birth to thousands of , which are dozens of times heavier than the Sun and then explode as supernovae when they die. Many supernovae explosions heat the gas around them to temperatures of more than a million degrees, and this hot gas flows out from the galaxy as galactic wind. These winds are so powerful that they may play an important role in the evolution of galaxies and the inter-galactic medium. However, galactic winds are usually diffuse and difficult to observe; therefore, it has been difficult to confirm their power. Nevertheless, it is possible to precisely estimate their energy level by measuring how far the galactic winds reach.

The current team tackled the issue of shedding light on the processes behind large-scale galactic winds by focusing their research on the "cap" of M 82, one of the closest starburst galaxies to Earth, about 12 million away. M 82 has large-scale galactic winds, so-called "superwinds", and its cap consists of about 40,000 light years away from its . Matsubayashi pinpointed the research question: "Why are there ionized gas clouds so far from the galactic disk? If we investigate the ionization source of the cap, we can confirm whether M 82's galactic winds reach it."

Two possibilities for ionization sources of M 82's cap are: 1) ultraviolet photons from massive stars in M 82's starburst regions and 2) shockwaves caused by the collision of M 82's galactic winds with gas clouds in the cap (Figure 1). The researchers reasoned, "Because we can estimate the intensity of ultraviolet photons from the starburst regions and the pressure of the galactic winds from past observational data, the morphology and H-alpha intensity of the cap region will reveal the answer."

The team investigated the ionization source of M 82's cap by observing it with Kyoto 3DII mounted on the . They used the Fabry-Perot interferometer, which works as a narrow-band filter that researchers can tune for a desired wavelength. They obtained images of continuum and H-alpha emissions of the cap. (Figure 2)

Figure 2: Images of the cap of M 82 (Credit: NAOJ) Left: H-alpha image of M 82. The contours represent the intensity of X-rays. The brightest region at the lower left of the panel is M 82's center. The diffuse emission region at the upper right is the cap. Center: Continuum image that shows the background area of the cap. The objects in this panel are stars in the Milky Way Galaxy or distant galaxies. There is no detection of a continuum emission from the cap. Right: H-alpha image of the cap. This shows the detection of H-alpha emission from the cap. It also shows that the cap is clumpy rather than uniform. The typical size of clumps is 300 - 500 light years in diameter.

If UV light from the M 82 starburst regions ionized the clumps of the cap, the H-alpha emission should be ten times weaker than what was observed. In contrast, the H-alpha intensity predicted by the shock model matches well with the measurement from the observations. Therefore, the team concluded that from M 82's galactic winds ionized the gas clouds in the cap. This suggests that the galactic winds travel and have direct impacts on inter-galactic gas at least 40,000 light years away from the galactic disk.

The research raises another question: "Do galactic winds affect gas clouds at an even further distance from the galactic disk?" Matsubayashi remarked, "We would like to carry out observations to survey more distant gas clouds ionized by ."

Explore further: When did galaxies settle down?

More information: The scientific results were published in the December 10, 2012 edition of The Astrophysical Journal: K. Matsubayashi et al., "Ionization Source of a Minor-Axis Cloud in the Outer Halo of M 82", 761:55 (8pp).

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vidyunmaya
1 / 5 (7) Jan 19, 2013
Information:12 million light years away. M 82 has large-scale galactic winds, 40,000 light years away from its galactic disk.
Comments: at this log-scale- the data is very useful- for Electromagnetic Listening post.Please provide clear pictures-Interpretations can be helped through Cosmology Vedas Interlinks.
This region must have Uplink mode as well for Knowledge Expansion.

cantdrive85
1 / 5 (7) Jan 20, 2013
Two possibilities for ionization sources of M 82's cap are: 1) ultraviolet photons from massive stars in M 82's starburst regions and 2) shockwaves caused by the collision of M 82's galactic winds with gas clouds in the cap.


Possibility 3) there is no reason to assume that the cloud wouldn't be ionized being that all of interstellar and intergalactic space is plasma. The cloud is in intergalactic space with plenty of free electrons and ions to ionize any such cloud.
robeph
4.3 / 5 (6) Jan 20, 2013
Or possibility 4, you're a moron. Yes, a there is indeed a good bit of ionized gas in the interstellar medium, however, to say all, ie. 100%, is rather silly. That being said, why do you continuously post? You never say anything of value, you never support anything you state beyond some sketchy looking websites that look more like tumblr than respectable science, and even was what you say 99% of the time verifiable, you do little to discuss the actual sciences and instead spend your whole time bitching about how wrong everyone else is. It's like those political idiots who go on and on about how doing X is wrong while never offering an more than a loosely parameterized alternative of little use than being suggested as a counter rather than something of value itself.
cantdrive85
1.8 / 5 (5) Jan 20, 2013
I've responded with peer-reviewed material and any number of other respected resources continuously, yet it seems too difficult for most to get their head around. This from the National Academy of Sciences;
"Plasma is the fourth state of matter and is ubiquitous in the universe. Plasmas pervade intergalactic space, interstellar space, interplanetary space, and the space environments of the planets. With the help of magnetic fields, plasma organizes itself into galactic jets, radio filaments, supernova bubbles, accretion disks, galactic winds, stellar winds, stellar coronas, sunspots, heliospheres, magnetospheres, and radiation belts. Magnetic fields partition space into tubes and shells of all sizes from galactic to planetary scales. Plasmas generate cosmic rays, stellar flares, coronal mass ejections, interstellar and interplanetary shock waves, magnetospheric storms, and a cacophony of radio waves."
http://www.nap.ed...p;page=5
It is ubiquitous, as they say!
cantdrive85
1.8 / 5 (5) Jan 20, 2013
"In volume, 99.999% of all the observable matter in the universe exists in the plasma state. This had led to the coinage of the term Plasma Universe."

Dr. Timothy Eastman

Being that the .001% is mostly the rocky planets, moons, asteroids, and such, it really doesn't leave much room for any significant amount of interstellar and intergalactic space to be anything other than plasma.
Tuxford
1 / 5 (5) Jan 20, 2013
Other potential sources of the ionization could include an unrecognized physical process that favors the long-term stability of ions in deep space. This seems to be a feature of SQK physics, for example. But suggesting such a thing would kill the career of any aspiring astronomer. Cowards abound in the community, but it is politically incorrect to say so.
Torbjorn_Larsson_OM
5 / 5 (4) Jan 20, 2013
It is easy to agree that it *is* moronic to reply to the vital question if there are peer reviewed support for EU/PC with references to the existence of plasma in the universe which everyone agrees on.

The reason we call EU/PC pseudoscience belief is because there is exactly zero research testing it.

And the reason we call it a religion is because proponents "never say anything of value, you never support anything you state beyond some sketchy looking websites that look more like tumblr than respectable science, ... you do little to discuss the actual sciences and instead spend your whole time bitching about how wrong everyone else is."

In this case obviously the research rejects EU/PC yet again.

Those who are actually interested in science is tired of religious trolls, take it to your religious websites and stay there.
Torbjorn_Larsson_OM
5 / 5 (2) Jan 20, 2013
Oh, for the love of science! More inanity:

@Tuxford: Your references to the existence and acceptance of alternate "SQK physics", please.

Of course aspiring astronomers would be wise to become astronomers before going on to make Nobel founding suggestions! For one, you aren't likely to stumble on something new until you have been in the business for a while.

But if they do stumble on something, it's intrinsic value shows itself. Examples would be Newton, Darwin, Wallace, Einstein, et cetera - having a degree but developing their research in seclusion at first.
Tuxford
1.7 / 5 (6) Jan 20, 2013
Oh, for the love of science! More inanity:


Oh, the self-appointed science police strikes again! Intellectual egomania abounds.
Torbjorn_Larsson_OM
5 / 5 (3) Jan 20, 2013
Oops, I forgot: the Galileo defense, "I am criticized, therefore I am correct", scores high on Baez's Crackpot Index. Ironically that captures the meanwhile hair trigger response too.

I don't go after trolls only because of my interest in science and education and trolls are hitting both, I also have a science degree which means I have a moral obligation to do so.

So forget "self-appointment", "intellectual" and "ego-mania", not supportable anyway since individuals aren't statistics, but now know to be rejected by observation. (Google Google Scholar and check.)
vidyunmaya
1 / 5 (2) Jan 21, 2013
Sub:Need to establish clear Knowledge Base
Our Local Cosmic Laboratory-http://www.nap.ed...p;page=5
Thanks for clear information. With this knowledge-Dimensional frame must set the tone
from:Plasma Regulated Electromagnetic phenomena in magnetic Field Environment-See detailed projections in my books
Welcome Interaction with like minded groups- visitor-chicago
http://vidyardhic...ion.html
Tuxford
1 / 5 (2) Jan 27, 2013
I also have a science degree which means I have a moral obligation to do so.


Add: self-righteous, self-appointed, intellectual egomaniac.

It is humorous to see such critics on par with religious egomaniacs, using the same superior moral authority as rationale for their positions. It is useless to argue with such small-minded individuals. They are lost already to their affliction.

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