Metropolitan Community College Early Undergraduate Research Program *********

Metropolitan Community CollegeMetropolitan Community College

Early Undergraduate Research ProgramEarly Undergraduate Research Program********* *********

Topic: Variation of the ShowerTopic: Variation of the Shower

OLOU AppolinaireOLOU Appolinaire

HypothesisHypothesis

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

Specific goal.Specific goal.

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

Meteorology and the Meteorology and the wind compass. wind compass.

““The wind compass The wind compass

is a tool used is a tool used

in meteorologyin meteorology

to track the wind”to track the wind”

ProceduresProcedures

A stack was builtA stack was built

for the detectors, for the detectors,

making sure they making sure they

are superposed.are superposed.

Procedure (cont’d)Procedure (cont’d)

The stack is tiltableThe stack is tiltable

a certain angle α a certain angle α

with regard to with regard to

the vertical.the vertical.

Experiment 1Experiment 1

Orientation is Northward, the reference Orientation is Northward, the reference position.position.

Angle of tilt α=20˚.Angle of tilt α=20˚. Rotational angle increase is pi/6 (30˚).Rotational angle increase is pi/6 (30˚). Rotation is clockwise.Rotation is clockwise. Timing is 10mn.Timing is 10mn.

Experiment 2Experiment 2

Orientation is Northward, the reference Orientation is Northward, the reference position.position.

Angle of tilt α=29.5˚.Angle of tilt α=29.5˚. Rotational angle increase is pi/4 (45˚).Rotational angle increase is pi/4 (45˚). Rotation is counterclockwise.Rotation is counterclockwise. Timing is 15mn.Timing is 15mn.

Graph 1: Rate Vs. Graph 1: Rate Vs. DirectionDirection

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N 30˚ 60˚ E 30˚ 60˚ S 30˚ 60˚ W 30˚ 60˚

Series1

Graph 2: Rate Vs. Graph 2: Rate Vs. DirectionDirection

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N 45˚ W 45˚ S 45˚ E 45˚

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Analysis of graphsAnalysis of graphs

Both graphs display the same pattern at the beginning.Both graphs display the same pattern at the beginning. In (1), highest counts are obtained from the south-60-In (1), highest counts are obtained from the south-60-

west to the north with two peaks occurring at north-30-west to the north with two peaks occurring at north-30-west and south-60-west.west and south-60-west.

In (2), highest counts are obtained from west-45-south In (2), highest counts are obtained from west-45-south to the north, with one peak at the south.to the north, with one peak at the south.

The overall pattern is not consistent.The overall pattern is not consistent. Experiment conditions have changed in both cases.Experiment conditions have changed in both cases.

Analysis (cont’d)Analysis (cont’d)

The average rate is about 2 ½ as much in The average rate is about 2 ½ as much in experiment 1 than in experiment 2 (64/mn experiment 1 than in experiment 2 (64/mn ± ± 7.8% 7.8% in (1), and 26/mn in (1), and 26/mn ±± 11.5% in (2). 11.5% in (2).

- Increase in timing in (2) cannot cut down the Increase in timing in (2) cannot cut down the rate.rate.

- The direction of the rotation (clockwise vs. The direction of the rotation (clockwise vs. counterclockwise) and the rotational angle counterclockwise) and the rotational angle increase (30 vs. 45) don’t also look to be increase (30 vs. 45) don’t also look to be factors.factors.

Analysis (cont’d)Analysis (cont’d)

The angle of tilt of the stack is possibly The angle of tilt of the stack is possibly the causing factor of the change in rate.the causing factor of the change in rate.

Additional experiment is needed to Additional experiment is needed to confirm this assumption.confirm this assumption.

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

Rate vs. Slope

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45

1 2 3 4 5 6 7

Angle

Rat

e Series1

Change in height .Change in height .

Rate vs. Height vs. angleRate vs. Height vs. angle

αα 15.15.8282

18.618.6 2121 26.526.566

30.930.966

3535 39.839.8

HH 134134.7.7

132.132.77

130.130.77

125125 120120 115115 107.107.66

RateRate 4343 4040 3737 3232 3131 3737 2828

DiscussionDiscussion

The rate vs. direction The rate vs. direction is not conclusive.is not conclusive.

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N 30˚ 60˚ E 30˚ 60˚ S 30˚ 60˚ W 30˚ 60˚

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N 45˚ W 45˚ S 45˚ E 45˚

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Discussion (cont’d)Discussion (cont’d)

As it traverses the atmosphere and As it traverses the atmosphere and approaches the ground, the shower becomes approaches the ground, the shower becomes less dense as a result of its dispersion or less dense as a result of its dispersion or spread.spread.

This suggests that depending on their altitude, This suggests that depending on their altitude, some regions may have more exposure than some regions may have more exposure than other, especially those on mountain top.other, especially those on mountain top.

Observations confirm this conclusionObservations confirm this conclusion

Victor Hess 1911-12 (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.Shower in real-life.

Further ProjectsFurther Projects

Quantitative comparison of the shower Quantitative comparison of the shower on roof top vs. at ground level.on roof top vs. at ground level.

Shower vs. days.Shower vs. days. Repeat the same project and collect data Repeat the same project and collect data

during same hour of day.during same hour of day.

- With a special care to the measurements With a special care to the measurements (angle, height).(angle, height).