INDEX 



The subject indexes of all STK volumes are conibined in a master index printed in a separate volume. 

 For access to the index volume consult the Army or Navy Agency listed on the reverse of the half-title page. 



"Absorption cross section" of bubble, 



466 

 Absorption effect in underwater sound 

 transmission 

 absorption coefficient, 97-100 

 attenuation measurements, 102-105 

 bubble formation, 465-467 

 coefficient of attenuation, 100 

 frequency ranges, 105-107 

 thermal structure, 102 

 transmission anomaly, 100-101 

 wakes, 541-543 

 Acoustic interference 

 echoes, 377 

 intensity, 168-170 

 target strength measurements, 410 

 Acoustic interferometer for sound ve- 

 locity measurements, 17 

 Acoustic measurements in underwater 

 transmission, 243-244, 474^77 

 Acoustic wakes 



see Bubbles in acoustic wakes; 

 Wakes, acoustic 

 Acoustical axis of sound projector, 26- 



27 

 Adiabatic pressure changes during 



bubble formation, 461 

 Aerial photographs in acoustic wake 



geometry, 494-495 

 Air bubbles in acoustic wakes 



see Bubbles in acoustic wakes 

 Airey phase of water waves, 232 

 Anchored ships, target strength meas- 

 urements, 424-425, 437 

 Angular variation of echo level, 546 

 Antinodes of stationary sound waves, 



33 

 Aspect angle, target strength measure- 

 ments, 388-393, 424 

 Asymmetry effects on target strength 



measurements, 400-402 

 Attenuation coefficient in sonic trans- 

 mission 

 bottom scattering, 320-321 

 bubble formation, 469-470 

 isothermal water, 100, 104-107 

 shadow boundary, 124-125 

 target strength measurements, 370, 



373,411-413 

 transmission anomaly, 129-131 

 wake thickness, 503-504, 508-509 

 Attenuation of sound 

 bubble theory, 533-534 

 explosions, 193-197 



frequency effects, 209-211 



long ranf e transmission, 216-219 



propeller wakes, 510-511 



scattering layer, 299-301 



shadow zone, 67-68 



transmission anomaly, 100, 105-107 



wake theory, 503-504 



wave theory, 27-28 

 Average layer effect in underwater 



sound transmission, 112 

 Averaging methods for reverberation 

 data, 278-280 



B-19 H magnetostrictive hydrophone, 



74 

 Backward scattering coefficient of 



sound, 252, 266, 306, 335 

 Backward scattering of sound, 254, 483 

 Band method of averaging reverber- 

 ation data, 279-280 

 Bathythermograph 



classification, 92-95 



description, 76 



ray tracing, 60-63 



velocity-depth variations, 197-200 

 Beam target strengths in echo ranging, 



415^17, 435^36 

 Bell Telephone Laboratories (BTL), 

 surface vessel target strengths, 

 423-424 

 Blade cavitation in acoustic wakes, 449 

 "Blobs" in reverberation of sound, 335 

 Bottom reverberation of sound, 264 



average intensities, 321-323 



data analysis, 319-321 



deep-water transmission, 86-87 



definition, 264 



description, 308-312 



frequency, 318-319 



grazing angle, 314-318 



refraction, 312-313 



scattering coefficients, 314, 319-321, 

 338 



summary, 338-339 

 Bottom scattering coefficients of sound, 



314, 319-321, 338 

 Bottom-reflected sound 



attenuation coefficient, 103-104 



dispersion phenomena, 228-229 



normal modes theory, 222-224 



predictions of ray theory, 224 



ray intensity, 55-56 



reflection coefficient, 219-221 



shallow-water transmission, 137-138 



simple harmonic propagation, 224- 

 227 



summary, 243 



supersonic frequencies, 140-141 



times of arrival, 221-222 



wave equation, 33-34 

 Boundary conditions in sound propa- 

 gation 



point source far from surface, 33-34 



point source near surface, 31-33 



reflection and refraction of plane 

 waves, 30-31 



reflection from sea bottom, 33-34 



target strengths, 353 



transition conditions, 28-31 



wake theoiy, 478 



wave equation, 13-14 

 BTL (Bell Telephone Laboratories), 

 surface vessel target strengths, 

 423^24 

 Bubbles in acoustic wakes 



absorption during bubble pulsation, 

 464^67 



acoustic effects, 474-477 



attenuation, 469-470 



"bubble hypothesis", 533 



buoyancy, 452^55 



damping constant, 467 



decay of wakes, 539-540 



echo intensities, 514-515 



entrained air, 455^57 



long pulses, 515-516 



multiple scattering, 470-473 



oscillograms, 186-190 



propeller cavitation, 449-452, 539 



reflection, 473^74 



scattering by an ideal bubble, 460- 

 464 



scattering coefficient, 306-307 



short pulses, 516-519 



submarine wake strengths, 538-539 



surface vessel wake strengths, ,537- 

 538 



theory, 448, 467-469 



transmission loss, 503-504, 533-535 



wake echoes, 535-537 

 Bulk modulus of a disturbed fluid, 12 

 Buoyancy of bubbles in underwater 



sound, 452-455 

 Burbling cavitation for bubble forma- 

 tion, 449 

 "Burning" process in underwater ex- 

 plosions, 173-174 



559 



