Rationale

Scientists are currently are at a crossroads in Galactic center research. Many recent large-scale surveys and wide-field studies of this unique and unusual region of the Galaxy have been made (using Chandra, HST/NICMOS, Spitzer, Fermi and numerous ground based observatories). Such surveys have provided us with multi-wavelength views of the stellar and interstellar environment in the central few hundred parsecs; additional surveys (filling in the gaps in the electromagnetic spectrum) are underway or being planned (EVLA, ALMA, Herschel, SOFIA, Planck, etc.). At the same time, unprecedented high-resolution views of the very central nuclear region are being constructed using the largest and most powerful telescopes on the ground (VLT-I, Keck, VLBA, EHT) providing us more details than ever before on the stellar population and the immediate environment of the 4 million solar mass black hole, SgrA*.

Many of the large- and small-scale phenomena observed are due to the influx of gas from the outer parts of the Galaxy and the feedback of energetic processes in the interstellar environment. Whereas the gas that resides in the Galactic Center represents about 10% of the the gas involved in star formation in the Galaxy, it only occurs in about 0.001% of the Galaxy's volume. It is likely that this gas has funneled to its present location during episodes in the lifetime of our Galaxy's bar. The gas in the Galactic Center is characterized by very high densities and turbulent conditions. The multi-phase gas is subject to strong and weak shocks as well as heating via dust, UV photons, cosmic rays and cloud-cloud collisions, all embedded within a strong and widespread magnetic field. Understanding the details of the interplay between stars and the interstellar medium and the role of cosmic rays in heating/interacting with the interstellar medium is crucial to our understanding of nuclear processes in many normal galaxies and in the cores of very distant galaxies.

We aim to bring together Galactic center researchers who are focused on trying to answer the following outstanding questions:

• What are the detailed physical properties of the clouds in the Central Molecular Zone and what is the potential for forming stars in this environment?

• What is the role of stellar feedback in our Galactic center and in starbursts?

• How well do we understand the accretion processes around Sgr A*, and the inner pc's of the Galactic center?

• What tracers do we have of Sgr A*'s prior AGN-like history?   Are the Fermi bubbles related, or due to stellar processes?

• What are we learning about the Galactic center environment from observations with new facilities such as ALMA, Fermi, NuSTAR, and new multiwavelength campaigns?

The IAU 303 Symposium builds upon a tradition in the Galactic Center community of holding a series of regular international meetings. One of the first international symposia on the Galactic Center was held in 1989 in Los Angeles, CA, USA (IAU #136). More recently, the IAU has sponsored a Symposium on the Galactic Center and nearby nuclei (IAU #184) in 1997, and the international Galactic Center community has put together meetings in 1998, 2002, 2006 and 2009. A priority at all of these meetings has been to create an atmosphere of international collaboration and a meeting in which ample time is reserved for productive discussions. These discussions have fostered interaction among all conference participants and has kept the Galactic center research community active, engaged and broadly spread across the world.

This 5-day symposium will be held in Santa Fe, New Mexico, USA during 30 Sept 2013 to 4 Oct 2013. Historically, the Galactic center meetings alternate locations worldwide (Japan (1997), Chile (1996), USA (1998), USA/Pacific (2002), Germany (2006), and China (2009). The USA is again prepared to host the proposed meeting in 2013.

A program of invited review presentations and contributed speakers will be complemented by poster sessions, extended workshop-like discussion sections and time for informal professional and social interactions. We note that a role of the SOC members will be to lead the discussion sections and not to give invited or review talks; those are reserved for the younger researchers and students.

The state capital of New Mexico, Santa Fe, is easily accessible by air and train through Albuquerque, New Mexico, USA. Santa Fe has many affordable options for lodging (especially in the Fall season, which is non-peak as skiing has not begun yet) and dining. In addition, since many of the LOC will be from Albuquerque and Socorro, NM, it will likely be possible to identify affordable and reliable child care options in Santa Fe, should participants be interested in this service.

Furthermore, Santa Fe is close to the NRAO-Socorro headquarters, which operates the newly commissioned EVLA and can be toured as part of the meeting. An exciting and popular cultural event during the meeting period is the Albuquerque International Balloon Fiesta as well as many Native American and Hispanic cultural sites throughout the state.