2 THIS PROPOSED STUDY WILL INVESTIGATE THE OCCURRENCE OF MID INFRARED EXCESSES FOUND IN WISE DATA IN LOW MASS FIELD STARS. THESE MIR EXCESSES ARE INTERPRETED AS DUST REPROCESSED STAR LIGHT, OCCURRING WHEN TERRESTRIAL PLANETARY BODIES COLLIDE. THESE SYSTEMS SERVE AS AN IMPORTANT SIGNATURES OF TERRESTRIAL PLANET FORMATION AND EVOLUTION. THIS PROPOSAL BUILDS OFF THE RESULTS OF A PILOT STUDY CONDUCTED USING WISE, 2MASS, AND SDSS OBSERVATIONS. THIS STUDY USED MIR OBSERVATIONS FROM WISE TO IDENTIFY 175 SPECTROSCOPICALLY CONFIRMED LOW MASS STARS EXHIBITING EXCESS MIR FLUX OVER EXPECTED STELLAR PHOTOSPHERIC LEVELS. THEISSEN & WEST INVESTIGATED OTHER EXPLANATIONS FOR STARS EXHIBITING EXCESS MIR FLUX. ACCOUNTING FOR ANY POSSIBLE CONTAMINANTS, 175 STARS WERE FOUND WITH MIR EXCESSES, AND A LOW PROBABILITY OF MIR EXCESSES BEING ATTRIBUTABLE TO A CONTAMINATING SOURCE. THROUGH INVESTIGATION OF THE DISK LUMINOSITIES AND APPROXIMATE STELLAR AGES ESTIMATED FROM SPECTROSCOPIC TRACERS, IT WAS DETERMINED THE MOST LIKELY CAUSE OF THE EXCESS MIR FLUX IS A LARGE ABUNDANCE OF CIRCUMSTELLAR MATERIAL, LIKELY CAUSED BY COLLISIONS BETWEEN PLANETARY BODIES. THE PILOT STUDY WAS LIMITED BY ITS SMALL SAMPLE SIZE AND INCOMPLETENESS DUE TO THE SDSS SPECTROSCOPIC TARGET SELECTION. OUR PROPOSED STUDY WILL USE A PHOTOMETRICALLY SELECTED SAMPLE TO CREATE A MORE COMPLETE AND STATISTICALLY SIGNIFICANT SAMPLE OF LOW MASS STARS EXHIBITING MIR EXCESSES. THE FIRST OBJECTIVE OF THIS PROPOSAL WILL BE TO CONSTRUCT A PHOTOMETRIC CATALOG OF LOW MASS STARS, COMBINING WISE, 2MASS, AND SDSS PHOTOMETRY. TO DIFFERENTIATE STARS FROM OTHER POINT-LIKE SOURCES OF SIMILAR COLOR, WE WILL USE PROPER MOTIONS. THE LARGE TIME BASELINES BETWEEN WISE, 2MASS, AND SDSS OBSERVATIONS ALLOW US TO COMPUTE RELIABLE PROPER MOTIONS FOR MILLIONS OF PHOTOMETRIC LOW MASS STARS CONTAINED WITHIN THE COMBINED DATASET. THE SECOND OBJECTIVE OF THIS PROPOSAL WILL BE TO SELECT STARS WITH APPARENT INFRARED EXCESSES, AND REMOVE SOURCES WITH ANY POSSIBLE CONTAMINANTS USING THE METHODS FROM THEISSEN & WEST, WHICH ARE EASILY SCALABLE TO MILLIONS OF SOURCES. THEISSEN & WEST USED TWO METHODS TO DETERMINE STARS WITH EXCESS MIR FLUX. THE FIRST METHOD IS COMPLETELY EMPIRICAL, USING VISIBLE AND INFRARED COLORS TO DIFFERENTIATE STARS WITH MIR EXCESSES FROM TYPICAL MAIN SEQUENCE COLORS. THIS METHOD CAN EASILY BE SCALED TO THE MILLIONS OF STARS EXPECTED IN THE PROPER MOTION CATALOG ABOVE. THIS PHOTOMETRIC SAMPLE WILL ALSO ALLOW US TO BETTER CONSTRAIN LOW-MASS STAR MAIN SEQUENCE COLORS DUE TO THE ORDERS OF MAGNITUDE LARGER NUMBER OF STARS CONTAINED WITHIN. THE SECOND METHOD IS TO FIT MODEL STELLAR SPECTRAL ENERGY DISTRIBUTIONS TO VISIBLE AND NEAR-INFRARED DATA IN ORDER TO CONSTRAIN THE STELLAR PARAMETERS. THIS WILL BE DONE USING A MONTE CARLO MARKOV CHAIN TO EXPLORE THE STELLAR PARAMETER SPACE AND CONSTRAIN A BEST FIT MODEL, WHILE ALSO PROVIDING AN UNCERTAINTY ESTIMATE ON EACH PARAMETER. A NUMBER OF MCMC FRAMEWORKS ARE AVAILABLE FOR US TO USE, AND WITH THE BOSTON UNIVERSITY SHARED COMPUTING CLUSTER, THIS METHOD IS ALSO SCALABLE TO MILLIONS OF SOURCES. THESE MODELS WILL ALLOW US TO ESTIMATE AN EXPECTED MIR FLUX, AND COMPARE THAT TO THE OBSERVED WISE MIR FLUX. LASTLY, USING A GALACTIC MODEL TO REPRODUCE EXPECTED STELLAR DENSITIES AND KINEMATICS, WE WILL DETERMINE THE EXPECTED NUMBER OF STARS PER LOCATION AND PROPER MOTION BIN. WE CAN COMPARE THIS MODEL TO OUR OBSERVED NUMBER COUNTS TO STUDY THE FREQUENCY OF LOW MASS FIELD STARS EXHIBITING IR EXCESSES, AND CONSTRAIN THE OCCURRENCE OF COLLISIONS IN PLANETARY SYSTEMS. Funding Only Action $40.2k 4/10/17 Not listed THIS PROPOSED STUDY WILL INVESTIGATE THE OCCURRENCE OF MID INFRARED EXCESSES FOUND IN WISE DATA IN LOW MASS FIELD STARS. THESE MIR EXCESSES ARE INTERPRETED AS DUST REPROCESSED STAR LIGHT OCCURRING WHEN TERRESTRIAL PLANETARY BODIES COLLIDE. THESE SYSTEMS SERVE AS AN IMPORTANT SIGNATURES OF TERRESTRIAL PLANET FORMATION AND EVOLUTION. THIS PROPOSAL BUILDS OFF THE RESULTS OF APILOT STUDY CONDUCTED USING WISE 2MASS AND SDSS OBSERVATIONS. THIS STUDY USED MIR OBSERVATIONS FROMWISE TO IDENTIFY 175 SPECTROSCOPICALLY CONFIRMED LOW MASS STARS EXHIBITING EXCESS MIR FLUX OVER EXPECTED STELLAR PHOTOSPHERIC LEVELS.THEISSEN & WEST INVESTIGATED OTHER EXPLANATIONS FOR STARS EXHIBITING EXCESS MIR FLUX. ACCOUNTING FOR ANY POSSIBLE CONTAMINANTS 175 STARS WERE FOUND WITH MIR EXCESSES AND A LOW PROBABILITY OF MIR EXCESSES BEING ATTRIBUTABLE TO A CONTAMINATING SOURCE. THROUGH INVESTIGATION OF THE DISK LUMINOSITIES AND APPROXIMATE STELLAR AGES ESTIMATED FROM SPECTROSCOPIC TRACERS IT WAS DETERMINED THE MOST LIKELY CAUSE OF THE EXCESS MIR FLUX IS A LARGE ABUNDANCE OF CIRCUMSTELLAR MATERIAL LIKELY CAUSED BY COLLISIONS BETWEEN PLANETARY BODIES. THE PILOT STUDY WAS LIMITED BY ITS SMALL SAMPLE SIZE AND INCOMPLETENESS DUE TO THE SDSS SPECTROSCOPIC TARGET SELECTION. OUR PROPOSED STUDY WILL USE A PHOTOMETRICALLY SELECTED SAMPLE TO CREATE A MORE COMPLETE AND STATISTICALLY SIGNIFICANT SAMPLE OF LOW MASS STARS EXHIBITING MIR EXCESSES.THE FIRST OBJECTIVE OF THIS PROPOSAL WILL BE TO CONSTRUCT A PHOTOMETRIC CATALOG OF LOW MASS STARS COMBINING WISE 2MASS AND SDSS PHOTOMETRY. TO DIFFERENTIATE STARS FROM OTHER POINT-LIKE SOURCES OF SIMILAR COLOR WE WILL USE PROPER MOTIONS. THE LARGE TIME BASELINES BETWEEN WISE 2MASS AND SDSS OBSERVATIONS ALLOW US TO COMPUTE RELIABLE PROPER MOTIONS FOR MILLIONS OF PHOTOMETRIC LOW MASS STARS CONTAINED WITHIN THE COMBINED DATASET.THE SECOND OBJECTIVE OF THIS PROPOSAL WILL BE TO SELECT STARS WITH APPARENT INFRARED EXCESSES AND REMOVE SOURCES WITH ANY POSSIBLE CONTAMINANTS USING THE METHODS FROM THEISSEN & WEST WHICH ARE EASILY SCALABLE TO MILLIONS OF SOURCES. THEISSEN & WEST USED TWO METHODS TO DETERMINE STARS WITH EXCESS MIR FLUX. THE FIRST METHOD IS COMPLETELY EMPIRICAL USING VISIBLE AND INFRARED COLORS TO DIFFERENTIATE STARS WITH MIR EXCESSES FROM TYPICAL MAIN SEQUENCE COLORS. THIS METHOD CAN EASILY BE SCALED TO THE MILLIONS OF STARS EXPECTED IN THE PROPER MOTION CATALOG ABOVE. THIS PHOTOMETRIC SAMPLE WILL ALSO ALLOW US TO BETTER CONSTRAIN LOW-MASS STAR MAIN SEQUENCE COLORS DUE TO THE ORDERS OF MAGNITUDE LARGER NUMBER OF STARS CONTAINED WITHIN.THE SECOND METHOD IS TO FIT MODEL STELLAR SPECTRAL ENERGY DISTRIBUTIONS TO VISIBLE AND NEAR-INFRARED DATA IN ORDER TO CONSTRAIN THE STELLAR PARAMETERS. THIS WILL BE DONE USING A MONTE CARLO MARKOV CHAIN TO EXPLORE THE STELLAR PARAMETER SPACE AND CONSTRAIN A BEST FIT MODEL WHILE ALSO PROVIDING AN UNCERTAINTY ESTIMATE ON EACH PARAMETER. A NUMBER OF MCMC FRAMEWORKS ARE AVAILABLE FOR US TO USE AND WITH THE BOSTON UNIVERSITY SHARED COMPUTING CLUSTER THIS METHOD IS ALSO SCALABLE TO MILLIONS OF SOURCES. THESE MODELS WILL ALLOW US TO ESTIMATE AN EXPECTED MIR FLUX AND COMPARE THAT TO THE OBSERVED WISE MIR FLUX.LASTLY USING A GALACTIC MODEL TO REPRODUCE EXPECTED STELLAR DENSITIES AND KINEMATICS WE WILL DETERMINE THE EXPECTED NUMBER OF STARS PER LOCATION AND PROPER MOTION BIN. WE CAN COMPARE THIS MODEL TO OUR OBSERVED NUMBER COUNTS TO STUDY THE FREQUENCY OF LOW MASS FIELD STARS EXHIBITING IR EXCESSES AND CONSTRAIN THE OCCURRENCE OF COLLISIONS IN PLANETARY SYSTEMS. $40.2k 4/10/17 1 THIS PROPOSED STUDY WILL INVESTIGATE THE OCCURRENCE OF MID INFRARED EXCESSES FOUND IN WISE DATA IN LOW MASS FIELD STARS. THESE MIR EXCESSES ARE INTERPRETED AS DUST REPROCESSED STAR LIGHT, OCCURRING WHEN TERRESTRIAL PLANETARY BODIES COLLIDE. THESE SYSTEMS SERVE AS AN IMPORTANT SIGNATURES OF TERRESTRIAL PLANET FORMATION AND EVOLUTION. THIS PROPOSAL BUILDS OFF THE RESULTS OF A PILOT STUDY CONDUCTED USING WISE, 2MASS, AND SDSS OBSERVATIONS. THIS STUDY USED MIR OBSERVATIONS FROM WISE TO IDENTIFY 175 SPECTROSCOPICALLY CONFIRMED LOW MASS STARS EXHIBITING EXCESS MIR FLUX OVER EXPECTED STELLAR PHOTOSPHERIC LEVELS. THEISSEN & WEST INVESTIGATED OTHER EXPLANATIONS FOR STARS EXHIBITING EXCESS MIR FLUX. ACCOUNTING FOR ANY POSSIBLE CONTAMINANTS, 175 STARS WERE FOUND WITH MIR EXCESSES, AND A LOW PROBABILITY OF MIR EXCESSES BEING ATTRIBUTABLE TO A CONTAMINATING SOURCE. THROUGH INVESTIGATION OF THE DISK LUMINOSITIES AND APPROXIMATE STELLAR AGES ESTIMATED FROM SPECTROSCOPIC TRACERS, IT WAS DETERMINED THE MOST LIKELY CAUSE OF THE EXCESS MIR FLUX IS A LARGE ABUNDANCE OF CIRCUMSTELLAR MATERIAL, LIKELY CAUSED BY COLLISIONS BETWEEN PLANETARY BODIES. THE PILOT STUDY WAS LIMITED BY ITS SMALL SAMPLE SIZE AND INCOMPLETENESS DUE TO THE SDSS SPECTROSCOPIC TARGET SELECTION. OUR PROPOSED STUDY WILL USE A PHOTOMETRICALLY SELECTED SAMPLE TO CREATE A MORE COMPLETE AND STATISTICALLY SIGNIFICANT SAMPLE OF LOW MASS STARS EXHIBITING MIR EXCESSES. THE FIRST OBJECTIVE OF THIS PROPOSAL WILL BE TO CONSTRUCT A PHOTOMETRIC CATALOG OF LOW MASS STARS, COMBINING WISE, 2MASS, AND SDSS PHOTOMETRY. TO DIFFERENTIATE STARS FROM OTHER POINT-LIKE SOURCES OF SIMILAR COLOR, WE WILL USE PROPER MOTIONS. THE LARGE TIME BASELINES BETWEEN WISE, 2MASS, AND SDSS OBSERVATIONS ALLOW US TO COMPUTE RELIABLE PROPER MOTIONS FOR MILLIONS OF PHOTOMETRIC LOW MASS STARS CONTAINED WITHIN THE COMBINED DATASET. THE SECOND OBJECTIVE OF THIS PROPOSAL WILL BE TO SELECT STARS WITH APPARENT INFRARED EXCESSES, AND REMOVE SOURCES WITH ANY POSSIBLE CONTAMINANTS USING THE METHODS FROM THEISSEN & WEST, WHICH ARE EASILY SCALABLE TO MILLIONS OF SOURCES. THEISSEN & WEST USED TWO METHODS TO DETERMINE STARS WITH EXCESS MIR FLUX. THE FIRST METHOD IS COMPLETELY EMPIRICAL, USING VISIBLE AND INFRARED COLORS TO DIFFERENTIATE STARS WITH MIR EXCESSES FROM TYPICAL MAIN SEQUENCE COLORS. THIS METHOD CAN EASILY BE SCALED TO THE MILLIONS OF STARS EXPECTED IN THE PROPER MOTION CATALOG ABOVE. THIS PHOTOMETRIC SAMPLE WILL ALSO ALLOW US TO BETTER CONSTRAIN LOW-MASS STAR MAIN SEQUENCE COLORS DUE TO THE ORDERS OF MAGNITUDE LARGER NUMBER OF STARS CONTAINED WITHIN. THE SECOND METHOD IS TO FIT MODEL STELLAR SPECTRAL ENERGY DISTRIBUTIONS TO VISIBLE AND NEAR-INFRARED DATA IN ORDER TO CONSTRAIN THE STELLAR PARAMETERS. THIS WILL BE DONE USING A MONTE CARLO MARKOV CHAIN TO EXPLORE THE STELLAR PARAMETER SPACE AND CONSTRAIN A BEST FIT MODEL, WHILE ALSO PROVIDING AN UNCERTAINTY ESTIMATE ON EACH PARAMETER. A NUMBER OF MCMC FRAMEWORKS ARE AVAILABLE FOR US TO USE, AND WITH THE BOSTON UNIVERSITY SHARED COMPUTING CLUSTER, THIS METHOD IS ALSO SCALABLE TO MILLIONS OF SOURCES. THESE MODELS WILL ALLOW US TO ESTIMATE AN EXPECTED MIR FLUX, AND COMPARE THAT TO THE OBSERVED WISE MIR FLUX. LASTLY, USING A GALACTIC MODEL TO REPRODUCE EXPECTED STELLAR DENSITIES AND KINEMATICS, WE WILL DETERMINE THE EXPECTED NUMBER OF STARS PER LOCATION AND PROPER MOTION BIN. WE CAN COMPARE THIS MODEL TO OUR OBSERVED NUMBER COUNTS TO STUDY THE FREQUENCY OF LOW MASS FIELD STARS EXHIBITING IR EXCESSES, AND CONSTRAIN THE OCCURRENCE OF COLLISIONS IN PLANETARY SYSTEMS. Funding Only Action $0 9/21/16 Not listed THIS PROPOSED STUDY WILL INVESTIGATE THE OCCURRENCE OF MID INFRARED EXCESSES FOUND IN WISE DATA IN LOW MASS FIELD STARS. THESE MIR EXCESSES ARE INTER $0 9/21/16 Not listed THIS PROPOSED STUDY WILL INVESTIGATE THE OCCURRENCE OF MID INFRARED EXCESSES FOUND IN WISE DATA IN LOW MASS FIELD STARS. THESE MIR EXCESSES ARE INTER $84.8k 3/4/16