This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy.
Skip to the content

Share this

Free weekly newswire

Sign up to receive all our latest news direct to your inbox.

Physics on film

100 Second Science Your scientific questions answered simply by specialists in less than 100 seconds.

Watch now

Bright Recruits

At all stages of your career – whether you're an undergraduate, graduate, researcher or industry professional – brightrecruits.com can help find the job for you.

Find your perfect job

Physics connect

Are you looking for a supplier? Physics Connect lists thousands of scientific companies, businesses, non-profit organizations, institutions and experts worldwide.

Start your search today

Blog

What’s that ‘fluctuation’ at 120 GeV?

By Hamish Johnston

Last week’s particle-physics conference in Paris began with the news that CERN’s Large Hadron Collider (LHC) may have produced the first glimpse of direct CP violation in a charmed-muon decay.

If that wasn’t enough to get particle physicists mildly excited, Friday’s joint announcement by the ATLAS and CMS experiments should do the trick.

Physicists working on the LHC’s two biggest experiments have pooled their data from 2011 (or at least the bits they have managed to analyse so far) to obtain the best mass exclusion yet for the Higgs boson.

The data reveal that the mass of the Higgs is unlikely to fall in the range 140–480 GeV/c2. This is news because most of this energy range had not been excluded by previous colliders, including the Tevatron at Fermilab. When combined with work at other colliders, the ATLAS and CMS data suggest that the Higgs mass falls into a window between about 110–140 GeV/c2, or is greater than about 480 GeV/c2.

Perhaps the most intriguing feature of the data is a sharp change at about 120 GeV/c2. In his blog, Tommaso Dorigo explains the significance of this fluctuation, and argues that it could be the first indication of the Higgs mass, which he believes is 119 GeV/c2. You can read Dorigo’s analysis here.

In the video above, physicists from the CMS experiment talk about the mass-exclusion results.

In other LHC news, researchers from the CMS experiment have published a paper in Physical Review Letters detailing the most extensive search for supersymmetry to date. Supersymmetry (or SUSY) is an attractive concept because it offers a solution to the “hierarchy problem” of particle physics, provides a way of unifying the strong and electroweak forces, and even contains a dark-matter particle. An important result of the theory is that every known particle has at least one superpartner particle, or “sparticle”.

Sadly, those waiting for a revolution in particle physics will have to wait a little longer, because no evidence for such sparticles has been found by CMS. You can read the paper here free of charge.

23 November Higgs update from CERN: Physicists on the ATLAS experiment have published a paper in Physical Review Letters that excludes the Standard Model Higgs mass from 340-450GeV/c2 at 95% confidence. You can read the paper here.

This entry was posted in General. Bookmark the permalink.
View all posts by this author  | View this author's profile

Leave a comment

Your e-mail address will not be published. Required fields are marked *

Guidelines

  • Comments should be relevant to the article and not be used to promote your own work, products or services.
  • Please keep your comments brief (we recommend a maximum of 250 words).
  • We reserve the right to remove excessively long, inappropriate or offensive entries.

Show/hide formatting guidelines

Tag Description Example Output
<a> Hyperlink <a href="http://www.google.com">google</a> google
<abbr> Abbreviation <abbr title="World Health Organisation" >WHO</abbr> WHO
<acronym> Acronym <acronym title="as soon as possible">ASAP</acronym> ASAP
<b> Bold <b>Some text</b> Some text
<blockquote> Quoted from another source <blockquote cite="http://iop.org/">IOP</blockquote>
IOP
<cite> Cite <cite>Diagram 1</cite> Diagram 1
<del> Deleted text From this line<del datetime="2012-12-17"> this text was deleted</del> From this line this text was deleted
<em> Emphasized text In this line<em> this text was emphasised</em> In this line this text was emphasised
<i> Italic <i>Some text</i> Some text
<q> Quotation WWF goal is to build a future <q cite="http://www.worldwildlife.org/who/index.html">
where people live in harmony with nature and animals</q>
WWF goal is to build a future
where people live in harmony with nature and animals
<strike> Strike text <strike>Some text</strike> Some text
<strong> Stronger emphasis of text <strong>Some text</strong> Some text
WordPress Appliance - Powered by TurnKey Linux