
	Where results make sense

Topic: Jeans mass

Related Topics

Gravitational collapse

Equivalence principle

In the News (Fri 18 Dec 09)

Northern Trust

Marvin Harrison

Peter Chernin

Gary Locke

Match Play

Penelope Cruz

Mickey Rourke

AR Rahman

Danny Boyle

Hugh Jackman

	Jeans instability - Wikipedia, the free encyclopedia
		is the enclosed mass, p is the pressure, G is the gravitational constant, r is the radius of the region
		Jeans mass is named after the British physicist Sir James Jeans, who considered the process of gravitational collapse within a gaseous cloud.
		Jeans instability occurs once the enclosed matter exceeds the Jeans mass or the region grows beyond the Jeans length.
	en.wikipedia.org /wiki/Jeans_mass (586 words)

	Protostar
		Protostars of around the mass of the Sun typically take 10 million years to evolve from a condensing cloud to a main-sequence star.
		Whatever the source of the disturbance, if it is sufficiently large it may cause the force due to gravity to become greater than the force due to thermal kinetic energy within a particular region of the cloud.
		He derived a formula for calculating the mass and size that a cloud would have to reach as a function of its density and temperature before gravitational contraction would begin.
	www.ebroadcast.com.au /lookup/encyclopedia/pr/Protostar.html (729 words)

	One Interpretation of the Correlation
		In particular, higher mass stars might be expected to be found near the centers of dense clusters if, during the initial accretion stages, cluster dynamical effects which enhance accretional growth are important.
		We then comment on previous speculation in the literature that the mass of the most massive star in a group might be related to protostellar dynamical evolution, and/or the critical mass for core fragmentation.
		The characteristic mass associated with the thermal length is the Jeans mass,
	donald.phast.umass.edu /theses/hillenbrand/clusters/node10.html (643 words)

	Jeans instability (Site not responding. Last check: 2007-10-10)
		Jeans (1902), however, proceeded to perform a perturbation analysis on the uniform infinite gas as if the unperturbed configuration satisfied the equilibrium equations.
		If a perturbation in a uniform gas involves a mass larger than the Jeans mass, then we expect the gas in the perturbed region to keep contracting due to the enhanced gravity.
		Jeans instability is the basic reason why the matter in the Universe is not spread uniformly.
	grus.berkeley.edu /~jrg/ay202/node147.html (799 words)

	JEANS MASS (Site not responding. Last check: 2007-10-10)
		Here R is the outer radius, M(r) the mass as a funtion of the distance from the center of the sphere and G the gravitational constant.
		The amount of particles can be estimated by dividing the total mass of the cloud by the average mass of a particle.
		This average mass can be taken to be some constant times the mass of a proton.
	www.geocities.com /trikkievic/physics/Jeans/Jeans.html (413 words)

	Steinn Sigurdsson - Astro 475(W) 33
		GEtool in OZ There are three primary mechanisms suggested for generating such a mass function, all essentially presume that there is local star formation within a larger mass of gas.
		A contrasting view, represents the mass spectrum of stars essentially being due to the spectrum of masses expected from a bottom-up formation scenario, where there is some universal minimum mass scale for protostars, and the more massive stars form from mergers of small lumps.
		The observations are consistent with this distribution independent of primary mass (up to the requirement that the secondary must orbit outside the surface of the primary), and independent of mass ratio.
	www.astro.psu.edu /users/steinn/Astro475/sem5.html (1696 words)

	Jeans mass Comparison Table (Site not responding. Last check: 2007-10-10)
		The measure of the inertia of an object, determined by observing the acceleration when a known force is applied.
		The gravitational force acting on an object is found to be proportional to its mass, as is the gravitational force that it exerts on other objects.
		The mass enclosed within a sphere of diameter equal to the Jeans length.
	www.site.uottawa.ca:4321 /astronomy/Jeansmass_table.html (91 words)

	Stars - Introduction
		Jeans length basically states that a molecular cloud of a particular size can become unstable and begin collapse.
		A proto-star that is less than 0.8 Solar masses becomes a Brown Dwarf and a proto-star that exceeds 100 Solar masses becomes a Wolf-Rayet star - a very unstable star that cannot hold on to its outer layers.
		As the Hydrogen atoms at the core of the proto-star are forced together by heat and pressure, the Coulomb Barrier is reached.
	astronomyonline.org /Stars/Introduction.asp (1096 words)

	Dr. Rhett Herman-Physics homework (Site not responding. Last check: 2007-10-10)
		I used this to derive the Jeans mass, the mass required for a spherical cloud to collapse under it's own gravity.
		And yes, the Jeans mass does depend on the three parameters of mass, average radius and temperature T, so one does have to do some semi-intelligent guesstimating here.
		The Jeans mass criterion leads to the conclusion that large massive clouds with low density will become galaxies (big things) while less massive clouds with high densities will become individual solar systems.
	www.radford.edu /~rherman/phys/hw42114.html (1027 words)

	Premium denim follows trickle-down theory
		Jeans that cost more than $75 make up only 4 percent of the $14.7 billion denim market, but their cultural impact is greater than their economic one, according to NPD Group, a New York-based marketing information company.
		This new generation of mass-market jeans is still made the old-fashioned factory way, but extra steps have been added, from silk-screening designs to heat-pressing rhinestones, making them almost indistinguishable from their luxury cousins - except for the name on the back.
		Now jeans are ubiquitous, as much at the office as at the club.
	www.azcentral.com /style/articles/113005denim_trickle.html (1051 words)

	Catholic Answers Forums - Wearing Jeans In Church
		Jeans are about the nicest pants I own- I don't own a suit or slacks, and I'm not going to buy them just to wear to church.
		I opt not to wear jeans to Mass because I wear jeans for everything other thing I go to; they are my most common form of attire and also my lowest form of attire.
		She ran out to the car just in time to go to Mass wearing the same jeans and t-shirt that she was accustomed to wearing in Louisiana (no time to change - they had to choose between letting her go "as is" or making everyone late).
	forums.catholic.com /printthread.php?t=64720 (6337 words)

	How Levi Strauss & Co. Puts an Original Spin on Mass Customization
		After years of being the top jeans producer, the company that invented the rugged, riveted denim pant is losing ground to dozens of competitors from private-label discounters, to rivals like VF Corp. (which owns the Lee and Wrangler brands), to designers like Calvin Klein and Tommy Hilfiger.
		's is doing some learning too, specifically leveraging the mass customization process to promote dialogue and interactivity with end-consumers to glean what value means to a jeans buyer at the same time that it educates them about how to customize their jeans.
		Mass customization will be as important to the 21st century as mass production was to the 20th century.
	members.tripod.com /yjfile/levi1.htm (3816 words)

	Web Analytics, Mass Customization, and Metadata Converge
		The original jeans had a different type of pocket and a different type of stitching.
		Though the defining traits of the jeans were new pockets and stitching, perhaps the fabric was what consumers responded to.
		The jeans manufacturer would be able to report on the highest-selling pocket type, stitching, material, color, cut, and zipper style.
	www.clickz.com /showPage.html?page=3488916 (849 words)

	Jeans, James Hopwood (1877-1946)
		Going on to astrophysics and cosmogony, he solved the problem of the behavior of rotating masses of compressible fluids, and addressed the origins of binary stars and the collapse of interstellar clouds (see Jeans length and Jeans mass).
		With Harold Jeffreys he developed the tidal hypothesis of the origin of the planets, which, in the 1920s and 1930s, led to a sharp decline in optimism among professional astronomers about the prospects for life beyond the Solar System.
		In 1929, Jeans abandoned research and became an outstanding popularizer of science and the philosophy of science.
	www.daviddarling.info /encyclopedia/J/JeansJ.html (300 words)

	Dress Up For Mass? - phatmass phorum
		I think it's ok to wear normal clothes to daily Mass since you might not be able to change (like if you go to Mass on your way to work or on lunch break).
		From: Miami, FL capris (this is miami) or pants or jeans with a nice (emphasis on "nice") shirt.
		Sometimes after Mass we'll decide to go for a walk in the park, out to eat, over to see a friend, or just straight home.
	www.phatmass.com /phorum/index.php?showtopic=7160 (1127 words)

	destinationKM.com: Built To Order (Site not responding. Last check: 2007-10-10)
		In many ways, mass customization harkens back to simpler days, when the local milk company would know to leave a gallon of skim milk at your door and two quarts of whole milk at the neighbor's.
		Enter mass customization, which for manufactured products promises to bring back the convenience of getting a suit that fits the way you like it, and the right kind of milk in the right quantities.
		Granted, the earliest industry to offer mass customization, likely without ever calling it that, was the automobile industry, which in its earlier days offered customers page after page of options a la carte, from air conditioning to push-button transmissions.
	www.destinationkm.com /articles/default.asp?ArticleID=683 (3036 words)

	[No title] (Site not responding. Last check: 2007-10-10)
		The number density of halos of different masses is given by the Press-Schechter theory OR by N-body numerical simulations.
		Within each halo diffuse gas is assumed to be shock-heated (or adiabatic compression depending on the mass of the object) to the virial temperature during the collapse of the halo.
		In major halo mergers, when the halo mass doubles, the remaining gas in the halo is reheated to the new virial temperature: the largest galaxy become the new central galaxy and the other haloes become satellite galaxies (if their dynamical friction times are bigger then the halo lifetime)
	casa.colorado.edu /~ricotti/cosmology/pag01a.html (434 words)

	Jeans length - Wikipedia, the free encyclopedia
		Jeans' Length is the critical radius of a cloud (typically a cloud of interstellar dust) where thermal pressure, which causes the cloud to expand, is balanced by the gravitational pressure that causes the cloud to collapse.
		is Boltzmann's constant, T is the temperature of the cloud, r is the radius of the cloud, m is the cloud's mass, G is the Gravitational Constant and ρ is the cloud's mass density (i.e.
		Jeans mass (a different statement of the same problem)
	en.wikipedia.org /wiki/Jeans_length (256 words)

	The Dependence of Star Formation on the Mean Thermal Jeans Mass
		This reduced the mean thermal Jeans mass of the cloud from 1 solar mass to 1/3 of a solar mass.
		The calculation models the collapse and fragmentation of a 50 solar mass molecular cloud that is 0.180 pc in diameter (approximately 0.6 light-years).
		At the initial temperature of 10 K with a mean molecular weight of 2.46, this results in an thermal Jeans mass of 1/3 of a solar mass.
	www.astro.ex.ac.uk /people/mbate/Cluster/cluster2.html (588 words)

	Introduction to Stellar Astrophysics
		The constants a and c are the radiation constant, and the speed of light respectively.
		(b) Using the equation of hydrostatic equilibrium, and the mass of a shell dm, estimate the central pressure of the Sun.
		(iv) Contrast your value of the Jeans mass with the observed stellar mass range, and show how fragmentation of the cloud may occur as the cloud collapses.
	www.astro.livjm.ac.uk /courses/exams/phys251_0100.html (804 words)

	justinmullins.com/Starbirth
		is known as the Jeans mass after the astrophysicist James Jeans who worked out the details in the early 20th century.
		Any cloud that has less mass than the critical value remains a cloud but one that has more always collapses.
		is the Boltzmann constant, G is the gravitational constant and m is the average mass of the molecules and atoms in the cloud.
	www.justinmullins.com /starbirth.htm (169 words)

	lecture3
		Hence, as the cloud collapses and the density grows, the Jeans mass decreases.
		Hence the Jeans mass is no longer decreasing with increasing cloud density, and fragmentation halts.
		Obviously, although the model of a homogenous cloud has led us to a useful criterion (the Jeans mass) for the collapse of a cloud under its own self-gravity, the model is too simplistic to explain in detail the formation of real stars.
	www.maths.qmw.ac.uk /~svv/lecture3.htm (1379 words)

	Jeans mass concept from the Astronomy knowledge base (Site not responding. Last check: 2007-10-10)
		Jeans mass concept from the Astronomy knowledge base
		has definition The critical mass a volume of space must contain before it will collapse under the force of its own gravity.
		has definition The mass enclosed within a sphere of diameter equal to the Jeans length.
	www.site.uottawa.ca:4321 /astronomy/Jeansmass.html (68 words)

	Star Formation Newsletter, Issue 68
		We derive upper bounds on the dust masses of these disks from the absence of continuum emission and upper bounds on the gas masses from the lack of CO emission.
		For a nonuniform grid, resolving a small fraction of a Jeans mass is less restrictive than resolving ¼ of a Jeans length in each coordinate direction; resolving all three Jeans lengths is desirable but not necessary in order to avoid artificial fragmentation.
		In any case, we conclude that intermediate mass stars contribute significantly to the overall HI produced in a burst of star formation, and the formation of PDRs reduces even more the number of O stars that can be produced by a molecular cloud.
	www-astro.phast.umass.edu /sfnews/no68/no68.html (9094 words)

	cloud - Hutchinson encyclopedia article about cloud (Site not responding. Last check: 2007-10-10)
		In the sky overhead are clouds at high altitude, formed from water vapour condensed into millions of tiny water droplets suspended in air.
		Water vapour condensed into minute water particles that float in masses in the atmosphere.
		Clouds, like fogs or mists, that occur at lower levels, are formed by the cooling of air containing water vapour, which generally condenses around tiny dust particles.
	encyclopedia.farlex.com /cloud (797 words)

	ETHZ Institute of Astronomy: What we do
		We are using very high-resolution (100million, non-equal mass particles)) simulations to study the dynamical effect of fl holes on dark halo structure, the hierarchical growth of fl holes, the chaotic growth of dark matter fl holes, and, by analysing our 3-d simulations, the "true" (as opposed to "observed" fl-hole-mass/velocity-dispersion relation.
		We are interested in studying the role of initial conditions, in particular the clustering of dust during the turbulent collapse of proto-planetary clouds and the impact of dust during the first stages of disk evolution.
		We are studying the orbital evolution and the mass growth of central galactic fl holes during mergers with a resolution of 1 pc in a box of hundreds of kpc.
	www.exp-astro.phys.ethz.ch /projects.html (3044 words)

	Casual slacks: denim deja vu? - discount stores seeking larger share of casual jeans market Discount Store News - Find ...
		The nation's discounters are experiencing a collective sense of deja vu as they begin to accelerate their growth plans for and diversify their assortments of casual slacks for men and women.
		In most cases, they are reminded of the explosive growth they have witnessed in the jeans category over the last ten years as the mass market moved from the secondary to the primary channel of distribution for jeans sales.
		A recent survey revealed that nearly two out of three (63 percent) mass market jeans shoppers were going elsewhere for their casual slacks.
	findarticles.com /p/articles/mi_m3092/is_n16_v37/ai_21076830 (914 words)

	Stars - Stellar Evolution
		A low mass star is any star that is less than 2.2 Solar masses.
		We have already introduced the concept of Jeans Mass and Jeans Length that places restrictions on the size of cloud prior to collapse.
		The point of separation between low mass and high mass stars is in the mass of the cloud itself.
	astronomyonline.org /Stars/Evolution.asp (751 words)

	wet her jeans :: Online Catalog
		Wet her jeans and restrictions), wet her jeans interventions to reduce tobacco-use initiation (increasing the unit price for tobacco products and multicomponent mass media campaigns), and six interventions to increase cessation (increasing the unit price for tobacco wet her jeans multicomponent mass media campaigns; provider reminder systems; provider.
		Information regarding applicability can be used to assess wet her jeans extent to which the intervention might be useful in a particular setting or population.
		Though limited, economic information --- to be provided wet her jeans wet her jeans full report in 2001 --- might be useful in identifying a) resource requirements for interventions, and b) interventions that meet public health goals more efficiently than other available options.
	1loveu.org /wet-her-jeans-2071.html (272 words)

Try your search on: Qwika (all wikis)