Friday, June 20, 2014

Have a safe day!

Friday, June 20

11:15 a.m.
All-hands meeting - Auditorium

3:30 p.m.

4 p.m.
Joint Experimental-Theoretical Physics Seminar - One West
Speaker: Silvia Pascoli, Durham University
Title: Neutrinos: Toward an Understanding of the Origin of Neutrino Masses and Mixing Beyond the Standard Model

7 p.m.
Fermilab Lecture Series - Auditorium
Particle Fever
Tickets: $7

Monday, June 23

2 p.m.
Particle Astrophysics Seminar - Curia II
Speaker: Chris Weaver, University of Wisconsin
Title: Evidence for High Energy Astrophysical Muon Neutrinos with IceCube

3:30 p.m.

4 p.m.
All Experimenters' Meeting - Curia II

Click here for NALCAL,
a weekly calendar with links to additional information.

Ongoing and upcoming conferences at Fermilab


Take Five

WeatherSlight chance of thunderstorms

Extended forecast
Weather at Fermilab

Current Security Status

Secon Level 3

Current Flag Status

Flags at full staff

Wilson Hall Cafe

Friday, June 20

- Breakfast: chocolate chip pancakes
- Breakfast: chorizo and egg burrito
- Backyard pulled-pork burger
- Smart cuisine: sweet and sour apricot chicken
- Barbecue pork spareribs
- Turkey and cucumber salad wraps
- Big beef or chicken burrito
- Beef and rice soup
- Texas-style chili
- Assorted pizza by the slice

Wilson Hall Cafe menu
Chez Leon

Friday, June 20
5:30 p.m.
- Haricots verts and grape tomato salad with creme fraiche dressing
- Lobster tails with champagne butter sauce
- Spaghetti squash with scallions
- Sauteed sugar snap peas
- Mixed berry pie

Wednesday, June 25
- Rotini, summer squash and prosciutto salad with rosemary dressing
- Fresh blueberry and vanilla yogurt parfait

Chez Leon menu
Call x3524 to make your reservation.


Fermilab Today

Director's Corner

Frontier Science Result

Physics in a Nutshell

Tip of the Week

User University Profiles

Related content


Fermilab Today
is online at:

Send comments and suggestions to:

Visit the Fermilab
home page

Unsubscribe from Fermilab Today

In Brief

Users Executive Committee accepting membership nominations through June 27

The 2014 election for membership in the Fermilab Users Executive Committee is approaching.

All Fermilab users interested in standing for election are invited to complete the nomination form. The nomination deadline is June 27.

UEC members are elected for a two-year term starting in September. Candidates will be asked to provide a short statement and a photograph for the electronic ballot by mid-July. Voting will be done via Indico in the beginning of August.

Please help distribute this message to any potential candidates. If questions arise, please contact the Users Office.

In Brief

DASTOW takes place today

Fermilab's Daughters and Sons to Work (DASTOW) day takes place during the first half of today. Families can enjoy the Mr. Freeze cryogenics show, a Fermilab Fire Department demonstration of firefighting skills and safety, and lunch in the Wilson Hall atrium. For a full schedule of events, visit the DASTOW Web page.

Photo of the Day

Queen bee's followers

A new queen honey bee, along with part of an older colony in search of a new home, landed in this tree on B Road and stayed there for several days before disappearing. Photo: Dave Shemanske, FESS
The bees formed a barrier around the queen to protect her during that time. Honey bees are pollinators and provide an important service by pollinating fruit on many crops around the world. Photo: Dave Shemanske, FESS
In the News

Quantum method closes in on gravitational constant

From Nature, June 18, 2014

Physicists have used the quantum nature of matter to obtain a highly precise value for the universal gravitational constant, the 'big G' that appears in Isaac Newton's law of how gravity pulls together everything, from planets to apples. Although the technique still needs refinements, physicists believe that in the future it will beat the precision of conventional methods — and hopefully solve apparent discrepancies between measurements that have long puzzled physicists.

In a study described today in Nature, researchers measured the minuscule gravitational tug between rubidium atoms and a 516-kilogram array of tungsten cylinders. The uncertainty in the latest measurement is 150 parts per million, or 0.015% — only slightly larger than that of the conventional method of determining G, which is to quantify the mutual pull of two macroscopic masses.

Read more

In the News

Entangled clocks could provide accurate world time standard

From Physics World, June 18, 2014

Plans for a global network of atomic clocks that are synchronized using quantum entanglement have been unveiled by physicists in the US. The resulting universal time standard would be more accurate than is currently possible with individual atomic clocks, and the network could also be used to do a range of fundamental and applied research, such as mapping the Earth's gravitational field or even testing new theories of gravity. While some of the technologies needed to build the network already exist, other elements still need further development.

Atomic clocks have revolutionized the world in ways that were unimaginable when the first atomic clock was built in 1949. The Global Positioning System (GPS), for example, uses atomic clocks to measure the travel time of signals from four satellites to a GPS receiver almost anywhere on Earth.

Read more

Frontier Science Result: CMS

Slicing parameter space with a razor

Supersymmetric particles produced in proton collisions might have any of a variety of decay patterns, but the total energy of all decaying particles corresponds to the mass of the first particle in the cascade.

Supersymmetry is hard to kill. It is more general than most theories of physics beyond the Standard Model: It is the basic idea that particles and forces are fundamentally the same thing but appear different because something creates an effective distinction between them, similar to the way that the Higgs boson creates an effective distinction between the electric and weak parts of the electroweak force. For supersymmetry, that "something" is unknown — many different models of supersymmetry breaking have been proposed and others could be thought up tomorrow. Each variant, including minor variations in numerical parameters, yields different decay patterns involving different cascades of particles.

Seekers of supersymmetry are faced with a dilemma: Pick a model of supersymmetry breaking and hope you're lucky enough to find it, or look at a quantity that is sensitive to a broad class of models, but with less statistical sensitivity. If you pick a specific model and don't find it, you can set a precise exclusion limit, but only on one model — supersymmetry itself remains elusive. Broad searches, on the other hand, are hard to formulate. You have to think of a signature that is shared by many supersymmetric models yet is different enough from the Standard Model to clearly claim a discovery or set a tight limit.

One technique, dubbed "the razor," shares aspects of both. It makes weak assumptions about the mechanism of supersymmetry breaking but also makes a sharp distinction between supersymmetric particles and the Standard Model. Assuming that supersymmetric particles are within reach of the LHC (like squarks and gluinos), and that they are produced in pairs (R-parity is not violated), and that they decay in cascading chains (as many variants of supersymmetry do), they would show up in LHC collisions as two rough bundles of particles, each with an energy that corresponds to the mass of the first supersymmetric particle in the chain. Different models predict different decay patterns within each bundle, but this technique looks only for the bundles.

A group of CMS scientists selected events using the razor technique and found them to be consistent with the Standard Model. This cuts out a broad range of supersymmetric models, many more than a focused technique would. There are still others that might evade the razor's weak assumptions, but the remaining space is getting thin.

Jim Pivarski

The U.S. physicists pictured above made significant contributions to this analysis.
These graduate students and postdocs from the University of California, Davis helped make the recent annual meeting of the US CMS collaboration a fantastic success.

Butts and Guts class - register today

Fermilab Lecture Series presents Particle Fever with Q&A - today

Study of Genesis through Ancient Eyes begins June 24

Sitewide domestic hydrant flushing - June 28-29

New updates available for Mac computers

FermiWorks training for managers

Registering your personal device to access the Fermilab network

Yoga classes on Mondays or Thursdays

Scottish country dancing meets Tuesdays in Ramsey Auditorium

International folk dancing meets Thursdays in Ramsey Auditorium

Outdoor soccer

Find new classified ads on Fermilab Today.