<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
		>
<channel>
	<title>Comments on: LHC Factoids</title>
	<atom:link href="http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/feed/" rel="self" type="application/rss+xml" />
	<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/</link>
	<description>Random samplings from a universe of ideas.</description>
	<lastBuildDate>Mon, 09 Nov 2009 05:46:49 -0600</lastBuildDate>
	<generator>http://wordpress.org/?v=2.8.4</generator>
	<sy:updatePeriod>hourly</sy:updatePeriod>
	<sy:updateFrequency>1</sy:updateFrequency>
		<item>
		<title>By: Is That a Particle Accelerator in Your Pocket, Or Are You Just Happy to See Me? &#124; Cosmic Variance</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20656</link>
		<dc:creator>Is That a Particle Accelerator in Your Pocket, Or Are You Just Happy to See Me? &#124; Cosmic Variance</dc:creator>
		<pubDate>Wed, 04 Oct 2006 22:03:30 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20656</guid>
		<description>[...] The Large Hadron Collider accelerates protons to an energy of 7000 GeV, which is pretty impressive. (A GeV is a billion electron volts; the energy in a single proton at rest, using E=mc2, is about 1 GeV.) But it requires a 27-kilometer ring, and the cost is measured in billions of dollars. The next planned accelerator is the International Linear Collider (ILC), which will be similarly grand in size and cost. People have worried, not without reason, that the end is in sight for experimental particle physics at the energy frontier, as it becomes prohibitively expensive to build new machines. [...]</description>
		<content:encoded><![CDATA[<p>[...] The Large Hadron Collider accelerates protons to an energy of 7000 GeV, which is pretty impressive. (A GeV is a billion electron volts; the energy in a single proton at rest, using E=mc2, is about 1 GeV.) But it requires a 27-kilometer ring, and the cost is measured in billions of dollars. The next planned accelerator is the International Linear Collider (ILC), which will be similarly grand in size and cost. People have worried, not without reason, that the end is in sight for experimental particle physics at the energy frontier, as it becomes prohibitively expensive to build new machines. [...]</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Bob</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20616</link>
		<dc:creator>Bob</dc:creator>
		<pubDate>Fri, 29 Sep 2006 17:13:53 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20616</guid>
		<description>Just to add a couple of factoids.  The CMS magnet operates at 4 Tesla.  The energy stored in the magnetic field is about 2.5GJ.  If this energy were converted to potential energy, it could lift the whole CMS experiment about 20 m.  Or, it could lift 28 tons to the top of Mt Everest...

And it is true that ATLAS can float.  However, you would have to wrap it in Saran wrap (a lot of Saran wrap!) first...

The trigger for the LHC is a fascinating and, to some extent, scary topic.  In my previous experiment at LEP, we accumulated about 4 million hadronic Z decays (among other events).  That was essentially all of the produced Z bosons.  We only missed a couple thousand.  And we even have a pretty good idea why we didn&#039;t trigger on those events.  In other words, our acceptance was about 100%.  At the LHC, the number of potentially interesting events produced will simply be too high:  on the order of 10 to 100 thousand events per second.  We only have the capability to record data at 100-300 Hz.  Thus we have to throw away the least interesting events, while ensuring that we record the really exciting ones like the Higgs events (should they exist).  A daunting task!</description>
		<content:encoded><![CDATA[<p>Just to add a couple of factoids.  The CMS magnet operates at 4 Tesla.  The energy stored in the magnetic field is about 2.5GJ.  If this energy were converted to potential energy, it could lift the whole CMS experiment about 20 m.  Or, it could lift 28 tons to the top of Mt Everest&#8230;</p>
<p>And it is true that ATLAS can float.  However, you would have to wrap it in Saran wrap (a lot of Saran wrap!) first&#8230;</p>
<p>The trigger for the LHC is a fascinating and, to some extent, scary topic.  In my previous experiment at LEP, we accumulated about 4 million hadronic Z decays (among other events).  That was essentially all of the produced Z bosons.  We only missed a couple thousand.  And we even have a pretty good idea why we didn&#8217;t trigger on those events.  In other words, our acceptance was about 100%.  At the LHC, the number of potentially interesting events produced will simply be too high:  on the order of 10 to 100 thousand events per second.  We only have the capability to record data at 100-300 Hz.  Thus we have to throw away the least interesting events, while ensuring that we record the really exciting ones like the Higgs events (should they exist).  A daunting task!</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Plato</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20623</link>
		<dc:creator>Plato</dc:creator>
		<pubDate>Fri, 29 Sep 2006 13:56:40 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20623</guid>
		<description>I mean for sure we tend to see this &quot;complexity of the information&quot; and let&#039;s not loose sight of the &quot;powers of ten?&quot;

For the lay person like myself this compartive relation of information dropped down to &quot;scale&quot; is important. As it puts into perspective the &quot;reality&quot; around us.

The value of the Qubit, and the lesson we may learn on how computerization may now meet new ways to decipher LIGO INformation?

&lt;a href=&quot;http://physicalworld.org/restless_universe/figs/fig_0_1lrg.jpg&quot; rel=&quot;nofollow&quot;&gt;&lt;blockquote&gt;Many physical quantities span vast ranges of magnitude. Figures 0.1 and 0.2 use images to indicate the range of lengths and times that are of importance in physics.&lt;/blockquote&gt;&lt;/a&gt;

So I find it difficult to image the relation in the complexity of the &quot;rain drop&quot; too a string? Yet, LHC serves it&#039;s purpose from the bottom up?:)</description>
		<content:encoded><![CDATA[<p>I mean for sure we tend to see this &#8220;complexity of the information&#8221; and let&#8217;s not loose sight of the &#8220;powers of ten?&#8221;</p>
<p>For the lay person like myself this compartive relation of information dropped down to &#8220;scale&#8221; is important. As it puts into perspective the &#8220;reality&#8221; around us.</p>
<p>The value of the Qubit, and the lesson we may learn on how computerization may now meet new ways to decipher LIGO INformation?</p>
<p><a href="http://physicalworld.org/restless_universe/figs/fig_0_1lrg.jpg" rel="nofollow"><br />
<blockquote>Many physical quantities span vast ranges of magnitude. Figures 0.1 and 0.2 use images to indicate the range of lengths and times that are of importance in physics.</p></blockquote>
<p></a></p>
<p>So I find it difficult to image the relation in the complexity of the &#8220;rain drop&#8221; too a string? Yet, LHC serves it&#8217;s purpose from the bottom up?:)</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: John Baez</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20625</link>
		<dc:creator>John Baez</dc:creator>
		<pubDate>Fri, 29 Sep 2006 06:18:02 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20625</guid>
		<description>I know most of you are sick of those Encyclopedia Brittannica comparisons by now, but a while back I made a little &lt;a href=&quot;http://math.ucr.edu/home/baez/information.html&quot; rel=&quot;nofollow&quot;&gt;webpage on quantities of information&lt;/a&gt;, and I&#039;m not going to let it go to waste:

# A gigabyte is about a billion bytes (actually 2^30 of them).

    * 1 gigabyte: the human genome, or a pickup truck full of books.

    * 20 gigabytes: a good collection of the works of Beethoven.

    * 100 gigabytes: a library floor of academic journals.

# A terabyte is about a trillion bytes (actually 2^40 of them).

    * 2 terabytes: an academic research library.

    * 6 terabytes: all academic journals printed in 2002.

    * 10 terabytes: the print collections of the U.S. Library of Congress.

    * 40 terabytes: all books printed in 2002.

    * 50 terabytes: all mass market periodicals printed in 2002.

    * 60 terabytes: all audio CDs released in 2002.

    * 80 terabytes: capacity of all floppy discs produced in 2002.

    * 140 terabytes: all newspapers printed in 2002.

    * 170 terabytes: the searchable portion of the World-Wide Web in 2002.

    * 250 terabytes: capacity of all zip drives produced in 2002.

# A petabyte is about 10^15 bytes (actually 2^50 of them).

    * 1.5 petabytes: all office documents generated in 2002.

    * 2 petabytes: all U.S academic research libraries.

    * 6 petabytes: all cinema release films in 2002.

    * 20 petabytes: all X-ray photographs taken in 2002.

    * 90 petabytes: the &quot;Deep Web&quot; in 2002.

    * 130 petabytes: capacity of all audio tapes produced in 2002.

    * 400 petabytes: all photographs taken in 2002.

    * 440 petabytes: all emails sent in 2002.

# An exabyte is about 10^18 bytes (actually 2^60 of them).

    * 1.3 exabytes: capacity of all videotapes produced in 2002.

    * 2 exabytes: capacity of all hard disks produced in 2002.

    * 5 exabytes: all the words ever spoken by human beings.

    * 6 exabytes: information in the genomes of all the people in the world.

You may think you don&#039;t need to look at my webpage now, but you&#039;re wrong! You have to look at it to see how much information it takes to completely describe the quantum state of a typical raindrop.</description>
		<content:encoded><![CDATA[<p>I know most of you are sick of those Encyclopedia Brittannica comparisons by now, but a while back I made a little <a href="http://math.ucr.edu/home/baez/information.html" rel="nofollow">webpage on quantities of information</a>, and I&#8217;m not going to let it go to waste:</p>
<p># A gigabyte is about a billion bytes (actually 2^30 of them).</p>
<p>    * 1 gigabyte: the human genome, or a pickup truck full of books.</p>
<p>    * 20 gigabytes: a good collection of the works of Beethoven.</p>
<p>    * 100 gigabytes: a library floor of academic journals.</p>
<p># A terabyte is about a trillion bytes (actually 2^40 of them).</p>
<p>    * 2 terabytes: an academic research library.</p>
<p>    * 6 terabytes: all academic journals printed in 2002.</p>
<p>    * 10 terabytes: the print collections of the U.S. Library of Congress.</p>
<p>    * 40 terabytes: all books printed in 2002.</p>
<p>    * 50 terabytes: all mass market periodicals printed in 2002.</p>
<p>    * 60 terabytes: all audio CDs released in 2002.</p>
<p>    * 80 terabytes: capacity of all floppy discs produced in 2002.</p>
<p>    * 140 terabytes: all newspapers printed in 2002.</p>
<p>    * 170 terabytes: the searchable portion of the World-Wide Web in 2002.</p>
<p>    * 250 terabytes: capacity of all zip drives produced in 2002.</p>
<p># A petabyte is about 10^15 bytes (actually 2^50 of them).</p>
<p>    * 1.5 petabytes: all office documents generated in 2002.</p>
<p>    * 2 petabytes: all U.S academic research libraries.</p>
<p>    * 6 petabytes: all cinema release films in 2002.</p>
<p>    * 20 petabytes: all X-ray photographs taken in 2002.</p>
<p>    * 90 petabytes: the &#8220;Deep Web&#8221; in 2002.</p>
<p>    * 130 petabytes: capacity of all audio tapes produced in 2002.</p>
<p>    * 400 petabytes: all photographs taken in 2002.</p>
<p>    * 440 petabytes: all emails sent in 2002.</p>
<p># An exabyte is about 10^18 bytes (actually 2^60 of them).</p>
<p>    * 1.3 exabytes: capacity of all videotapes produced in 2002.</p>
<p>    * 2 exabytes: capacity of all hard disks produced in 2002.</p>
<p>    * 5 exabytes: all the words ever spoken by human beings.</p>
<p>    * 6 exabytes: information in the genomes of all the people in the world.</p>
<p>You may think you don&#8217;t need to look at my webpage now, but you&#8217;re wrong! You have to look at it to see how much information it takes to completely describe the quantum state of a typical raindrop.</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Velcro City Tourist Board &#187; Blog Archive &#187; Links for 29-09-2006</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20626</link>
		<dc:creator>Velcro City Tourist Board &#187; Blog Archive &#187; Links for 29-09-2006</dc:creator>
		<pubDate>Fri, 29 Sep 2006 02:20:49 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20626</guid>
		<description>[...] 12 - LHC Factoids &#8220;The well-known &quot;circular&quot; collider is actually not a circle. It consists of 8 straight sections and of 8 arcs.&#8221; Gen up on the Large Hadron Collider at Cosmic Variance! (tags: particle physics science trivia data misconceptions myths facts Collider Hadron Large LHC) [...]</description>
		<content:encoded><![CDATA[<p>[...] 12 &#8211; LHC Factoids &#8220;The well-known &#8220;circular&#8221; collider is actually not a circle. It consists of 8 straight sections and of 8 arcs.&#8221; Gen up on the Large Hadron Collider at Cosmic Variance! (tags: particle physics science trivia data misconceptions myths facts Collider Hadron Large LHC) [...]</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Tony Smith</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20624</link>
		<dc:creator>Tony Smith</dc:creator>
		<pubDate>Thu, 28 Sep 2006 20:43:26 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20624</guid>
		<description>JoAnne, you said &quot;... We had a great lecture on the [ LHC ] triggers at the SLAC Summer Institute and I&#039;ve started a draft of a post on the subject. ...&quot;.

The pdf by Paris Sphicas at
http://www-conf.slac.stanford.edu/ssi/2006/lec_notes/Sphicas072606.pdf
is very interesting, and I am sure that you heard much more at the actual talks and discussion, so I am looking forward to your post on triggering.

Will you also discuss cuts, another important stage of filtering what will actually be analyzed at LHC?

Tony Smith
http://www.valdostamuseum.org/hamsmith/</description>
		<content:encoded><![CDATA[<p>JoAnne, you said &#8220;&#8230; We had a great lecture on the [ LHC ] triggers at the SLAC Summer Institute and I&#8217;ve started a draft of a post on the subject. &#8230;&#8221;.</p>
<p>The pdf by Paris Sphicas at<br />
<a href="http://www-conf.slac.stanford.edu/ssi/2006/lec_notes/Sphicas072606.pdf" rel="nofollow">http://www-conf.slac.stanford.edu/ssi/2006/lec_notes/Sphicas072606.pdf</a><br />
is very interesting, and I am sure that you heard much more at the actual talks and discussion, so I am looking forward to your post on triggering.</p>
<p>Will you also discuss cuts, another important stage of filtering what will actually be analyzed at LHC?</p>
<p>Tony Smith<br />
<a href="http://www.valdostamuseum.org/hamsmith/" rel="nofollow">http://www.valdostamuseum.org/hamsmith/</a></p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Plato</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20628</link>
		<dc:creator>Plato</dc:creator>
		<pubDate>Thu, 28 Sep 2006 18:24:52 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20628</guid>
		<description>While most of us will remain at a distance from this research and development, we can learn much by the factoids and links too, what is accessible and produced for the public?

Beyond Einstein, and from Seti it was learnt? Why not use &quot;other&quot; computers?

You take the chance on blogging, to see the benefits later on?:) A new student , a lay person, who now can&#039;t get enough. More then, just the &quot;pizza guy&quot; and  or the &quot;toppings&quot; for sure. And we have this developing theory from what has already been produced in experimental research?

How appropriate.

http://pancake.uchicago.edu/%7Ecarroll/images/cms1.jpg

&lt;b&gt;Sean Carroll&lt;/b&gt;:&lt;a href=&quot;http://preposterousuniverse.blogspot.com/2005_06_01_preposterousuniverse_archive.html#111824861201647958&quot; rel=&quot;nofollow&quot;&gt;&lt;blockquote&gt;As a theorist (and one who grew up in astronomy departments), one of the most fascinating concepts in high-energy experiments is that of a trigger. Each detector will witness approximately one billion collisions per second, which is a lot. You might imagine that you&#039;re faced with two problems: simply recording all the data from each event, and then sifting through them for the interesting bits. You&#039;re right, but it&#039;s much worse than you think. That&#039;s because each event isn&#039;t just a few bytes if data; it&#039;s of order one megabyte per event. There&#039;s simply no way you could record all of the data.
&lt;/blockquote&gt;&lt;/a&gt;</description>
		<content:encoded><![CDATA[<p>While most of us will remain at a distance from this research and development, we can learn much by the factoids and links too, what is accessible and produced for the public?</p>
<p>Beyond Einstein, and from Seti it was learnt? Why not use &#8220;other&#8221; computers?</p>
<p>You take the chance on blogging, to see the benefits later on?:) A new student , a lay person, who now can&#8217;t get enough. More then, just the &#8220;pizza guy&#8221; and  or the &#8220;toppings&#8221; for sure. And we have this developing theory from what has already been produced in experimental research?</p>
<p>How appropriate.</p>
<p><a href="http://pancake.uchicago.edu/%7Ecarroll/images/cms1.jpg" rel="nofollow">http://pancake.uchicago.edu/%7Ecarroll/images/cms1.jpg</a></p>
<p><b>Sean Carroll</b>:<a href="http://preposterousuniverse.blogspot.com/2005_06_01_preposterousuniverse_archive.html#111824861201647958" rel="nofollow"><br />
<blockquote>As a theorist (and one who grew up in astronomy departments), one of the most fascinating concepts in high-energy experiments is that of a trigger. Each detector will witness approximately one billion collisions per second, which is a lot. You might imagine that you&#8217;re faced with two problems: simply recording all the data from each event, and then sifting through them for the interesting bits. You&#8217;re right, but it&#8217;s much worse than you think. That&#8217;s because each event isn&#8217;t just a few bytes if data; it&#8217;s of order one megabyte per event. There&#8217;s simply no way you could record all of the data.
</p></blockquote>
<p></a></p>
]]></content:encoded>
	</item>
	<item>
		<title>By: JoAnne</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20627</link>
		<dc:creator>JoAnne</dc:creator>
		<pubDate>Thu, 28 Sep 2006 17:47:36 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20627</guid>
		<description>Anna: you go girl!  I couldn&#039;t have said it better.  And, yes, actually seeing the detectors is awe inspiring.  I saw CMS last summer and hope to get to CERN sometime before next summer to see ATLAS and CMS underground, before everything is locked up.</description>
		<content:encoded><![CDATA[<p>Anna: you go girl!  I couldn&#8217;t have said it better.  And, yes, actually seeing the detectors is awe inspiring.  I saw CMS last summer and hope to get to CERN sometime before next summer to see ATLAS and CMS underground, before everything is locked up.</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Lidt facts om CERN&#8217;s Large Hadron Collider &#171; Lusepuster</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20619</link>
		<dc:creator>Lidt facts om CERN&#8217;s Large Hadron Collider &#171; Lusepuster</dc:creator>
		<pubDate>Thu, 28 Sep 2006 11:13:58 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20619</guid>
		<description>[...] PÃ¥ den fantastiske blog Cosmic Variance har jeg fundet dette indlÃ¦g,Â  som fortÃ¦ller lidt facts om den enorme partikelaccelerator, Large Hadron Collider, som er under opfÃ¸relse pÃ¥ (eller retttere under) CERN i Schweiz. [...]</description>
		<content:encoded><![CDATA[<p>[...] PÃ¥ den fantastiske blog Cosmic Variance har jeg fundet dette indlÃ¦g,Â  som fortÃ¦ller lidt facts om den enorme partikelaccelerator, Large Hadron Collider, som er under opfÃ¸relse pÃ¥ (eller retttere under) CERN i Schweiz. [...]</p>
]]></content:encoded>
	</item>
	<item>
		<title>By: Quasar9</title>
		<link>http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/comment-page-1/#comment-20620</link>
		<dc:creator>Quasar9</dc:creator>
		<pubDate>Thu, 28 Sep 2006 09:46:53 +0000</pubDate>
		<guid isPermaLink="false">http://blogs.discovermagazine.com/cosmicvariance/2006/09/27/lhc-factoids/#comment-20620</guid>
		<description>Hi Marty, I like that
125 DVDs or full feature length movies a second.
7500 movies recorded in &lt;b&gt;1&lt;/b&gt; minute. Every minute.
-
I guess scientists who review the data (movies) could be called film critics.
That&#039;s a lot of movie (data) watching.
-
Mind you 10 libraries of Congress every minute that is definitely gonna take some reading. So these triggers will be like librarians or clerks in the patents office.
&lt;b&gt;Perhaps the triggers should be called little Einsteins&lt;/b&gt;
-</description>
		<content:encoded><![CDATA[<p>Hi Marty, I like that<br />
125 DVDs or full feature length movies a second.<br />
7500 movies recorded in <b>1</b> minute. Every minute.<br />
-<br />
I guess scientists who review the data (movies) could be called film critics.<br />
That&#8217;s a lot of movie (data) watching.<br />
-<br />
Mind you 10 libraries of Congress every minute that is definitely gonna take some reading. So these triggers will be like librarians or clerks in the patents office.<br />
<b>Perhaps the triggers should be called little Einsteins</b><br />
-</p>
]]></content:encoded>
	</item>
</channel>
</rss>
