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In this issue:
From the Director of SSRL: The Next User Run
Symposium Honors Roger Blandford
PeopleSoft Downtime Today through Monday
Word of the Week: Pauli Exclusion Principle

SLAC Today

Friday - October 23, 2009

From the Director of SSRL:
The Next User Run

(Photo - Piero Pianetta)

The past few months have been an extremely busy time at the Stanford Synchrotron Radiation Lightsource. Not only have we been taking care of numerous shutdown activities and getting ready for users to start up again, but we have been working out the details to transition the SSRL Accelerator Division as a core team in the new Accelerator Directorate, as well as moving into the new financial system. To my pleasant surprise, not only have we all accomplished these varied tasks on a fast time scale but we have also learned how to better work together as a lab and develop a vision of the next steps we must take. 

I can attest to Persis' recent comment about the creation of the Accelerator Directorate that "we didn't break anything." The SPEAR3 core team is now firmly planted in the directorate and the startup of SPEAR3 has gone very smoothly with the Beamline, Accelerator and Radiation Protection groups coordinating their activities to make sure that a high-quality beam is delivered safely to users during the coming weeks.  Read more...

Symposium Honors Roger Blandford

(Photo - Blandford symposium in Kavli Auditorium)
(Photo by Marcia Rieke.)

Saturday, October 17, the Kavli Auditorium filled near capacity for a symposium celebrating the 60th birthday of astrophysicist Roger Blandford, director of the Kavli Institute for Particle Astrophysics and Cosmology. The event, entitled "Exploring the High Energy Universe," featured presentations by Blandford's colleagues, exploring the numerous (and much-cited) scientific advances, richness of professional activities, and congeniality of a remarkable career to date. A dinner at the nearby Rosewood Sand Hill Resort capped off the celebration.

Attendees reported a lively symposium filled with reviews of ambitious science and reminiscences about an outstanding scientist. SLAC astrophysicist Greg Madejski recalled a comment heard during a coffee break:

"How could this symposium not be a great success? Roger is so accomplished—yet so kind (and those attributes don't always go together). Everyone wanted to be a part of it!"

For more attendee perspectives, see the online event guest book.

PeopleSoft Downtime Today through Monday

PeopleSoft Financials will be unavailable today at noon through Monday at 8 a.m. This weekend, the project team will be establishing PeopleSoft on new hardware that will provide the user community with greater reliability and better application performance. This project is part of a lab-wide effort to provide a more robust financial systems infrastructure.  Read more...

Word of the Week: Pauli Exclusion Principle

An atom of nitrogen contains two electrons in its first energy level and five in its second—two in an "s" orbit, two in a "p" obrit and a lone electron in another "p" orbit.

The Pauli Exclusion Principle, formulated by Wolfgang Pauli in 1925, says that all particles in a quantum system must be in non-identical states. It applies only to a class of particles called fermions, which includes protons, neutrons, electrons, quarks and neutrinos. An example of the principle is each electron around an atomic nucleus having a unique orbital state. Two electrons with opposite spins can occupy each orbit and the electrons space themselves outward from the center.

This subatomic rule has consequences in some gigantic objects. The enormous density in a white dwarf star—a million times that of the sun—squeezes together all electrons so closely that they try to occupy the same state. The electrons stack up, exerting a pressure that counteracts gravity’s crushing pull and holds the star stable.


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