Metropolitan Community College Early Undergraduate Research Program ********* Topic: Variation of the Shower OLOU Appolinaire

Hypothesis Hypothesis The primary cosmic ray, because isotropic, may result into secondary ray, on the earth, the shower of which may be evenly distributed.

Specific goal. Investigate the Intensity of the Shower Vs. Direction.

Meteorology and the wind compass. “The wind compass is a tool used in meteorology to track the wind”

Procedures  A stack was built for the detectors, for the detectors, making sure they are superposed. are superposed.

Procedure (cont’d) The stack is tiltable a certain angle α with regard to the vertical.

Experiment 1  Orientation is Northward, the reference position.  Angle of tilt α=20˚.  Rotational angle increase is pi/6 (30˚).  Rotation is clockwise.  Timing is 10mn.

Experiment 2  Orientation is Northward, the reference position.  Angle of tilt α=29.5˚.  Rotational angle increase is pi/4 (45˚).  Rotation is counterclockwise.  Timing is 15mn.

Graph 1: Rate Vs. Direction

Graph 2: Rate Vs. Direction

Analysis of graphs  Both graphs display the same pattern at the beginning.  In (1), highest counts are obtained from the south-60- west to the north with two peaks occurring at north-30- west and south-60-west.  In (2), highest counts are obtained from west-45-south to the north, with one peak at the south.  The overall pattern is not consistent.  Experiment conditions have changed in both cases.

Analysis (cont’d)  The average rate is about 2 ½ as much in experiment 1 than in experiment 2 (64/mn ± 7.8% in (1), and 26/mn ± 11.5% in (2). -Increase in timing in (2) cannot cut down the rate. -The direction of the rotation (clockwise vs. counterclockwise) and the rotational angle increase (30 vs. 45) don’t also look to be factors.

Analysis (cont’d)  The angle of tilt of the stack is possibly the causing factor of the change in rate.  Additional experiment is needed to confirm this assumption.

Experiment 3: Rate vs. Slope (Angle of tilt)

Change in height.

Rate vs. Height vs. angle α H Rate

Discussion The rate vs. direction is not conclusive.

Discussion (cont’d)  As it traverses the atmosphere and approaches the ground, the shower becomes less dense as a result of its dispersion or spread.  This suggests that depending on their altitude, some regions may have more exposure than other, especially those on mountain top.  Observations confirm this conclusion

Victor Hess (quoted by Prof. Dan Clae, Unl) radiation (later known as cosmic ray) more intense above 150 meters than at sea level intensity doubled between 1000 m to 4000 m increased continuously through 5000 meters

Shower in real-life.

Further Projects  Quantitative comparison of the shower on roof top vs. at ground level.  Shower vs. days.  Repeat the same project and collect data during same hour of day. -With a special care to the measurements (angle, height).