As someone who has spent several years thinking hard about how to detect “hidden particles” — ones that are not affected by the three forces of the Standard Model, the electromagnetic force and the strong and weak nuclear forces — I am pleased to see the result that just appeared from the APEX experiment, at the Jefferson Laboratory in the US state of Virginia:
http://arxiv.org/PS_cache/arxiv/pdf/1108/1108.2750v1.pdf.
Quoting from [and modifying for non-experts, in italics] the abstract:
- We present a search at Jefferson Laboratory for new particles, lighter than protons, that are carriers of a new force and that can decay to electron-positron pairs [recall positron = anti-electron]. Such a particle can be produced by slamming an electron beam into ordinary matter... Using APEX data, we searched … and found no evidence of such a particle in a certain range of masses and force strengths. Our findings demonstrate that experiments of this type can explore a new, wide, and important range of masses and strengths for sub-proton-mass forces.
What they’re doing is looking for a particle that is similar to a Z particle, one of the carriers of the weak nuclear force, but that on the one hand (a) exerts a smaller force on ordinary matter than does the weak nuclear force, and on the other hand (b) is lighter in mass than the Z, so the force it exerts dies off more slowly with distance than does the weak nuclear force. If such a particle were found, it would represent the first new force of nature discovered in many decades!
A competitor experiment from Mainz (called MAMI) reported results a few months ago. The two experiments are sensitive to a comparable force strength and to slightly different mass ranges. You can see their results in the figure, which shows the APEX search region in blue and the MAMI search region in green, and other experiments in variants of grey. These two experiments are probing weaker forces — looking for force carrier particles that are more hidden — than has ever been possible before.
Both of these experiments are still in the very early days; their results come from short, preliminary runs of data-taking. They both plan to have a much longer run, which should allow them much greater sensitivity to weaker forces and to force carriers of a wider range of masses. In particular, the unshaded region in the figure, which hasn’t been searched yet, should be entirely covered soon.
I am also pleased because among the leaders on the APEX experiment are three young theorists, Rouven Essig, (a former Rutgers student of my colleague Scott Thomas, and now a Stonybrook faculty member), Natalia Toro and Philip Schuster (two of my co-authors on a recent paper, and faculty members at the Perimeter Institute), and an experimentalist and professor at nearby New York University, the ubiquitous Kyle Cranmer (who also is on ATLAS and presented that experiment’s result on the search for the Higgs particle a few weeks ago.)
Congratulations, APEX!!!
25 Responses
Thanks for another informative blog. Where else may I get that kind of info
written in such an ideal manner? I’ve a project that I’m simply now running on, and I’ve been at
the look out for such information.
I just couldn’t go away your site before suggesting that I actually enjoyed the usual info a person provide in your guests?
Is going to be again regularly to investigate cross-check new posts
My brother recommended I might like this website. He was once entirely right.
This publish actually made my day. You cann’t imagine simply how a lot time I had spent for this info!
Thank you!
If some one wants to be updated with latest technologies then he must be visit this website and
be up to date daily.
Thanks for finally talking about >New Experimental Result Searching
for Hidden Particles | Of Particular Significance <Loved it!
Such menus generally provide a approach to turn subtitles
don and doff. It was two power drills moving towards him at eye level.
As a separating shot here are the words associated with super-star Whoopi
Clooney: I demand clash of clans hack, nothing a lot more nothing less.
What’s up to every single one, it’s really a good for me to pay
a quick visit this site, it consists of precious
Information.
Hello Dear, are you in fact visiting this web site regularly,
if so thhen yyou will without doubt get good experience.
It’s going to be end of mine day, except before ending I
am reading this wonderful paragraph to increase my experience.
The manager Carlo Ancelotti has also proved to be. United
had no contact from Liverpool, away, the English top flight.
85 05 crore and co duong link nao vao m88 khong also won eighteen League
titles and have won it. Arsenal suffered a co duong link nao vao
m88 khong hamstring injury during last night’s
Champions League qualification for the second half was not so good for the Championship Playoffs.
Your style is unique in comparison tto other people I’ve read
stuff from. Many thaznks for posting when you’ve got the opportunity,
Guess I’ll just book mark this blog.
I’m not sure exactly why but this site is loading
extremely slow for me. Is anyone else having this issue or is it a
issue on my end? I’ll check back later on and see if the
problem still exists.
Hi are using WordPress for your site platform? I’m new to the blog world but I’m
trying to get started and set up my own. Do you need any coding expertise to make your own blog?
Any help would be greatly appreciated!
This page cesrtainly has aall of the information and fwcts I wanted about thiks subject and didn’t know
who to ask.
It’s an amazing paragraph in favor of all the internet viewers; they will obtain benefit
from it I am sure.
Hi there to every body, it’s myy first payy a visit of this blog; this webpage consists of awesome
and really excellent data in support of visitors.
Excellent article. I’m facing some of these issuess as well..
Appreciate the recommendation. Let me try itt out.
Hello there good afternoon, i want to franchise to this business and
do this personally, is it possible to get one more
contact number because I am unable to get into your contacts
composed above… would love to hear from you ASAP… many
thanks annd Our god bless
That is a good tip particularly to those fresh to the blogosphere.
Brief but very accurate information… Appreciate your sharing this one.
A must read post!
I am not sure where you are getting your info, but good
topic. I needs to spend some time learning more or understanding more.
Thanks for great information I was looking for this information for my mission.
It’s going to be end of mine day, however before end I
am reading this great post to increase my experience.
Ӏt’s difficult tо find educated people іn this рarticular topic, ƅut you sopund like yoս
know what you’re talking about! Ҭhanks
Exceptional post but I was wondering if you could write
a litte more on this topic? I’d be very thankful if you could
elaborate a little bit further. Appreciate it!