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In this issue:
The LCLS Races Forward
Colloquium Today: The Many Facets of Snowflakes: A Close Look at the Genesis of Pattern and Form
Compact Florescent Light Giveaway
Sail-away Science

SLAC Today

Monday - November 12, 2007

The LCLS Races Forward

(Photo - construction)

Construction crews working on the Linac Coherent Light Source (LCLS) site are busier than ever these days. Last week, the Beam Transport Hall, which bisects the research yard, began receiving the final yards of concrete for the roof after being connected to the Undulator Hall. On the other side of the hill, the Central Utilities Plant (CUP) is taking shape next to the Near Experimental Hall. You can keep track of the action in real-time with the LCLS webcams.

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(Photo - construction)
Colloquium Monday

The Many Facets of Snowflakes: A Close Look at the Genesis of Pattern and Form

(Photo - snowflakes)
Snowflake images courtesy of Ken Libbrecht and

Our understanding of the dynamics of growing crystals is remarkably primitive, and it is generally not possible to explain why even ordinary crystals develop their characteristic shapes. A case in point is the snow crystal (a.k.a. the snowflake), which grows into a puzzling variety of unusual morphologies under different conditions. Although snow crystals result from a simple phase transition, some basic aspects of their growth have remained unexplained—even at a qualitative level—for over 75 years.

In this afternoon's colloquium, Ken Libbrecht of Caltech will present snowflakes like you've never seen them before, explain how to grow electric ice needles in the lab, and discuss what this all means for the fundamental physics of crystal growth and pattern formation.

The colloquium will take place at 4:15 p.m. today in Panofsky Auditorium. All are invited to attend.

Compact Florescent Light Giveaway

(Photo - girl scout with light bulb)

Today at the cafeteria you can perk up your energy with lunch, and save energy with a free light bulb. From noon until 1:00 p.m., Girl Scout Troup 2350 from Redwood City will be handing out free compact florescent light bulbs.

"This is a great way to give back to our faithful cookie customers," notes Girl Scout father Chuck Boeheim.

According to the Girl Scouts of Northern California, their partnership with The Climate Project, Sierra Club and PG&E has created the largest compact fluorescent light bulb (CFL) giveaway ever.

Because CFLs use 80 percent less energy, they help reduce carbon dioxide emissions and are an important part of efforts to stop global warming. Last month, the Department of Energy encouraged lab employees to install CFLs in their homes.

Sail-away Science

Bebo White and Tom Abel will embark on a "Geek Cruise" this winter, entertaining holiday-makers with lectures on computer science and astrophysics.

For many people, a cruise of the western Caribbean is an opportunity for sun-splashed daydreaming, guiltless beach reading and lackadaisical dips in warm, shimmering waters—in other words, complete mental repose. But after SLAC's Bebo White and Tom Abel board the MS Veendam for the "Bright Horizons" cruise next January, an entire boatload of holiday-makers will voyage across those same waters with a slightly different agenda.

White and Abel, with the help of four other renowned scientists and two editors from Scientific American, will be filling the days onboard the Veendam with stimulating lectures, immersing participants of this "Geek Cruise" in a challenging intellectual environment. The lectures—25 in all, ranging from 90 minutes to 3 hours—will cover a wide range of topics, from computational science and astrophysics to evolution and archaeology.

"It's a really fun experience," said White, who lectured on his first Geek Cruise, Website Waves, a year and a half ago. "One of the best things about it is between lectures, you talk with everyone at dinner, on deck and during day trips, so you really become a close-knit group."

Most Geek Cruises are more focused than Bright Horizons—for example, Linux Lunacy, Mac Mania, Perl Wind and Chess Moves. "With those cruises," says White, "you need to teach them a skill. There's nothing like that on this one. We're trying to appeal to their curiosity, and make the subject interesting enough so if they want to know more they can pursue it further."

Bright Horizons will be Abel's first cruise—Geek or otherwise—and he is looking forward to bringing his lectures to this unique environment. "I'm excited," he remarked. "It's always great to have a chance to share the fun science you do with the public."

The western Caribbean's cultural richness and tropical charm, of course, cannot be ignored by even the Geekiest of minds. All participants of the Geek Cruise, a co-production of Insight Cruises and Scientific American, will enjoy full-day excursions at the ports-of-call—Key West, Belize City, Santo Tom├ís de Castilla and Cozumel.

"All the talks and programs are during the period at sea," said White, "so when you get to the ports, everyone can play tourist. That way, the lectures really only cut into your casino time." 

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