WE PROPOSE K2 PHOTOMETRY OF 12 BINARIES WITH ALGOL-TYPE LIGHT CURVES IN CAMPAIGN FIELD 18 (C18) TO STUDY GAS STREAM IMPACT AND SPOT DYNAMICS THAT INFLUENCE THE EVOLUTION OF THESE SYSTEMS. THESE TARGETS HAVE BEEN APPROVED FOR K2 C18 (PROGRAM GO18056). ALL OBSERVATIONS ARE IN THE LC MODE EXCEPT FOR ONE IMPORTANT TARGET S CNC FOR WHICH WE REQUEST ADDITIONAL SC COVERAGE. MOST EARLYTYPE STARS BEGIN AS BINARY OR MULTIPLE STAR SYSTEMS SO AN UNDERSTANDING THE EVOLUTION OF THE ALGOL SYSTEMS IS CRITICAL FOR A MORE GENERAL KNOWLEDGE OF MASSIVE STAR AND GALACTIC EVOLUTION. IN C18 WE WILL HAVE THE OPPORTUNITY TO REVISIT TWO INTERESTING BINARIES THAT WERE OBSERVED IN BOTH C5 AND C16 (S CNC AND RY CNC) AND LOOK FOR LONG-TERM VARIABILITY. S CNC IS A WELL STUDIED LATE-TERM ALGOL THAT DISPLAYS A TOTAL ECLIPSE. THE PRIMARY IN THIS SYSTEM HAS CLEARLY BEEN SPUN UP DURING ITS EVOLUTION AND THE SYSTEM IS MOST ASSUREDLY IN THE LATTER STAGES OF MASS TRANSFER. MODELS OF EACH LIGHT CURVE COMPUTED FROM THE WILSON-DEVINNEY PROGRAM WILL YIELD NOT ONLY THE STELLAR PARAMETERS BUT ALSO PARAMETERS FOR ACCRETION HOT SPOTS AND MAGNETIC SPOTS ON THE SECONDARY. THE K2 MISSION AND THE MODELING CAPABILITIES OF THE WILSON-DEVINNEY (WD) BINARY SYSTEM ANALYSIS PROGRAM PRESENT A UNIQUE OPPORTUNITY TO PROBE GAS STREAM DYNAMICS AND/OR MAGNETIC ACTIVITY FROM THE RECENTLY DISCOVERED QUADRATURE BRIGHTNESS VARIATIONS IN ALGOL BINARIES THAT WE CALL L/T VARIABLES. L/T IS THE FLUX RATIO BETWEEN THE QUADRATURE FLUX AT PHASE 0.25 TO THAT AT PHASE 0.75 (LEADING AND TRAILING HEMISPHERES ON THE PRIMARY STAR). THE L/T PHENOMENON WAS DISCOVERED IN KEPLER DATA AND HAS NEVER BEEN REPORTED IN GROUND-BASED PHOTOMETRY. L/T BEHAVIOR IS LIKELY DUE TO CHANGES IN EITHER HOT ACCRETION OR COOL MAGNETIC SPOTS. IN THE HOT SPOT INTERPRETATION THE IMPACT SITE'S LOCATION AND MOVEMENT CAN BE DIAGNOSTIC OF STREAM DYNAMICS THAT MAY BE MODULATED BY MAGNETIC FIELDS. IN THE COOL SPOT SCENARIO THE VARIABILITY IS A CONSEQUENCE OF MAGNETIC ACTIVITY ON THE MASS LOSER. NEW DATA FROM K2 CYCLE 6 (C18) WILL IMPROVE OUR STATISTICAL STUDY OF THE PERCENTAGE OF ALGOLS THAT SHOW L/T INEQUALITY AND INDICATE WHETHER THERE IS A PREFERENCE FOR L>T OR THE REVERSE. MODELING THE K2 LIGHT CURVES WITH THE WD PROGRAM STELLAR AND SPOT PARAMETERS INCLUDING SPOT MOTIONS WILL BE DETERMINED SO AS TO GENERATE AN IMAGE OF THE BINARY VERSUS TIME. WE PLAN TO APPLY FOR OBSERVING TIME AT KPNO TO OBTAIN SPECTRA THAT WILL SUPPORT THE K2 OBSERVATIONS. UPDATES TO THE WD PROGRAM WILL CONTINUE TO BE MADE AVAILABLE TO THE COMMUNITY.
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