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Exponential decay

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A quantity may decay via two or more different processes simultaneously. In general, these processes (often called "decay modes", "decay channels", "decay routes" etc.) have different probabilities of occurring, and thus occur at different rates with different half-lives, in parallel. The total decay
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of corresponding processes. Terms "partial half-life" and "partial mean life" denote quantities derived from a decay constant as if the given decay mode were the only decay mode for the quantity. The term "partial half-life" is misleading, because it cannot be measured as a time interval for which a
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is exposed to a medium of another temperature, the temperature difference between the object and the medium follows exponential decay (in the limit of slow processes; equivalent to "good" heat conduction inside the object, so that its temperature remains relatively uniform through its volume). See
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a retirement fund will decay exponentially being subject to discrete payout amounts, usually monthly, and an input subject to a continuous interest rate. A differential equation dA/dt = input – output can be written and solved to find the time to reach any amount A, remaining in the
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This is the form of the equation that is most commonly used to describe exponential decay. Any one of decay constant, mean lifetime, or half-life is sufficient to characterise the decay. The notation λ for the decay constant is a remnant of the usual notation for an
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After excitation, the emission intensity – which is proportional to the number of excited atoms or molecules – of a luminescent material decays exponentially. Depending on the number of mechanisms involved, the decay can be mono- or
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Thus, the amount of material left is 2 = 1/2 raised to the (whole or fractional) number of half-lives that have passed. Thus, after 3 half-lives there will be 1/2 = 1/8 of the original material left.
2362: 934: 2999:, the agent of interest might be situated in a decay chain, where the accumulation is governed by exponential decay of a source agent, while the agent of interest itself decays by means of an exponential process. 3469:
assigns each route a weight that gets bigger each time the route changes its state and decays exponentially with time. When the weight reaches a certain limit, no more flapping is done, thus suppressing the
701: 1210: 2477: 2167: 1540: 1061: 352: 143: 1909: 1001: 812: 214: 1374: 444: 1112: 2976:{\displaystyle T_{1/2}={\frac {\ln 2}{\lambda _{c}}}={\frac {\ln 2}{\lambda _{1}+\lambda _{2}+\lambda _{3}}}={\frac {t_{1}t_{2}t_{3}}{(t_{1}t_{2})+(t_{1}t_{3})+(t_{2}t_{3})}}.} 2112: 3186: 3309:
to a different state, the number of atoms in the original state follows exponential decay as long as the remaining number of atoms is large. The decay product is termed a
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In the pharmacology setting, some ingested substances might be absorbed into the body by a process reasonably modeled as exponential decay, or might be deliberately
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of exponential decay (when the capacitor is charged from a constant voltage source though a constant resistance). The exponential time-constant for the process is
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A more intuitive characteristic of exponential decay for many people is the time required for the decaying quantity to fall to one half of its initial value. (If
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such as light or X-rays or gamma rays in an absorbent medium, follows an exponential decrease with distance into the absorbing medium. This is known as the
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of an element of the assembly is the time elapsed between some reference time and the removal of that element from the assembly, the mean lifetime is the
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A quantity undergoing exponential decay. Larger decay constants make the quantity vanish much more rapidly. This plot shows decay for decay constant (
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makes an interesting example of multiple decay processes, with each resistor representing a separate process. In fact, the expression for the
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The mean lifetime can be looked at as a "scaling time", because the exponential decay equation can be written in terms of the mean lifetime,
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Many decay processes that are often treated as exponential, are really only exponential so long as the sample is large and the
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Graphs comparing doubling times and half lives of exponential growths (bold lines) and decay (faint lines), and their 70/
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and, even more, broadcasting useless information to peer routers. To prevent this undesired behavior, an algorithm named
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A very similar equation will be seen below, which arises when the base of the exponential is chosen to be 2, rather than
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decreases approximately exponentially with increasing height above sea level, at a rate of about 12% per 1000m.
736: 280:, it is possible to compute the average length of time that an element remains in the set. This is called the 158: 17: 1554: 1326: 3189: 383: 55: 1384: 1072: 603:) is discrete, then this is the median life-time rather than the mean life-time.) This time is called the 3235: 3496: 2733:
For a decay by three simultaneous exponential processes the total half-life can be computed as above:
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Exponential decay occurs in a wide variety of situations. Most of these fall into the domain of the
476: 3711: 3598: 1486:{\displaystyle 1=\int _{0}^{\infty }c\cdot N_{0}e^{-\lambda t}\,dt=c\cdot {\frac {N_{0}}{\lambda }}} 3148: 3064: 1550: 1914: 486: 3115: 3010: 2723:{\displaystyle T_{1/2}={\frac {\ln 2}{\lambda _{c}}}={\frac {\ln 2}{\lambda _{1}+\lambda _{2}}}.} 1118: 1007: 3203: 3593: 3453:
controlling that path has to repeatedly add and remove the path record from its routing table (
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of two resistors in parallel mirrors the equation for the half-life with two decay processes.
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by a constant factor, the same equation holds in terms of the two corresponding half-lives:
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of the amount of time before an object is removed from the assembly. Specifically, if the
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Furthermore, the particular case of a capacitor or inductor changing through several
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Given an assembly of elements, the number of which decreases ultimately to zero, the
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to its current value. Symbolically, this process can be expressed by the following
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holds. For small samples, a more general analysis is necessary, accounting for a
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Leike, A. (2002). "Demonstration of the exponential decay law using beer froth".
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The solution to this equation is given in the previous section, where the sum of
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for the mathematics of chains of exponential processes with differing constants
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Some vibrations may decay exponentially; this characteristic is often found in
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can be deviated to. When one of these paths repeatedly changes its state from
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languages requires additional assumptions, independent of exponential decay).
3340: 3296: 3224: 3052: 1266: 291: 2357:{\displaystyle \tau _{c}={\frac {\tau _{1}\tau _{2}}{\tau _{1}+\tau _{2}}}.} 3302: 3289: 3252: 3242: 3109: 940: 929:{\displaystyle \tau ={\frac {t_{1/2}}{\ln(2)}}\approx 1.4427\cdot t_{1/2}.} 3685: 3637: 3230: 30: 3348: 3330: 3323: 3310: 3262: 3256: 3212: 1246: 3093: 3072: 590: 315:, relates to the decay rate constant, λ, in the following way: 3422: 3199: 3060: 2577: 47: 3351:
system will simply return to equilibrium via an exponential decay.
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It is found that many administered substances are distributed and
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is the time at which the population of the assembly is reduced to
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The decline in resistance of a Negative Temperature Coefficient
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is equal to the half-life divided by the natural log of 2, or:
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Serway, Raymond A.; Moses, Clement J.; Moyer, Curt A. (1989),
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has a half-life of 138 days, and a mean lifetime of 200 days.
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Differential Equations with Applications and Historical Notes
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Decrease in value at a rate proportional to the current value
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In terms of separate decay constants, the total half-life
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associated with individual processes is by definition the
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of the decay routes; thus, in the case of two processes:
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For example, if the initial population of the assembly,
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is the initial quantity, that is, the quantity at time
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McGraw-Hill Encyclopedia of Science & Technology
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is the combined or total half-life for the process,
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In this case, λ is the eigenvalue of the 1226:, is obtained by evaluating the equation at 1056:{\displaystyle {\frac {dN}{N}}=-\lambda dt.} 347:{\displaystyle \tau ={\frac {1}{\lambda }}.} 138:{\displaystyle {\frac {dN}{dt}}=-\lambda N.} 3632: 3564: 1904:{\displaystyle \lambda _{1}+\lambda _{2}\,} 996:{\displaystyle {\frac {dN}{dt}}=-\lambda N} 258: 1383:be the normalizing factor to convert to a 525:(0), is 1000, then the population at time 3597: 3369:froth obeys the law of exponential decay. 3159: 3155: 3128: 2080:of corresponding partial decay constant: 1911:is treated as a new total decay constant 1900: 1689: 1642: 1450: 1365: 1269:. The units of the decay constant are s. 1201: 1103: 807:{\displaystyle N(t)=N_{0}2^{-t/t_{1/2}}.} 377:, instead of the decay constant, λ: 209:{\displaystyle N(t)=N_{0}e^{-\lambda t},} 1369:{\displaystyle N=N_{0}e^{-\lambda t},\,} 29: 3676: 3552: 2367:Since half-lives differ from mean life 726:in the exponential equation above, and 439:{\displaystyle N(t)=N_{0}e^{-t/\tau },} 14: 3724: 3359:Ludwig Maximilian University of Munich 3575: 3188:The same equations can be applied to 1320:Starting from the population formula 947:Solution of the differential equation 706:When this expression is inserted for 1237:is defined as being the quantity at 1107:{\displaystyle \ln N=-\lambda t+C\,} 3403: 3039: 3002:These systems are solved using the 148:The solution to this equation (see 24: 3373: 1662: 1599: 1413: 607:, and often denoted by the symbol 25: 3743: 3700: 3433:in order to remember the paths a 3108:) and similarly charges with the 3013:to have such a release profile. 38:) of 25, 5, 1, 1/5, and 1/25 for 3476: 2107:{\displaystyle \tau =1/\lambda } 1557:. We can compute it here using 263: 74:) is a positive rate called the 3541:Serway, Moses & Moyer (1989 1273:Derivation of the mean lifetime 3569: 3558: 3546: 3534: 3172: 3166: 2964: 2941: 2935: 2912: 2906: 2883: 2049: 2036: 2007: 1981: 1957: 1951: 1848: 1822: 1773: 1767: 1726:Decay by two or more processes 1215:where the final substitution, 1140: 1134: 890: 884: 749: 743: 687: 681: 660: 654: 561: 555: 396: 390: 171: 165: 13: 1: 3626: 3337:damped mechanical oscillators 3181:{\displaystyle R\,C\,\ln(2).} 1317:of the individual lifetimes. 821:Therefore, the mean lifetime 3707:Exponential decay calculator 3326:as temperature is increased. 2987:Decay series / coupled decay 1931:{\displaystyle \lambda _{c}} 1385:probability density function 584: 511:{\displaystyle \log _{2}{e}} 7: 3636:(10th ed.). New York: 3578:European Journal of Physics 3504: 3192:of current in an inductor. 3138:{\displaystyle \tau =R\,C,} 10: 3748: 3717:Tutorial on time constants 3608:10.1088/0143-0807/23/1/304 3407: 3075:reactions behave this way. 1737:rate of the quantity  1729: 1301:, (also called simply the 588: 268:If the decaying quantity, 76:exponential decay constant 54:if it decreases at a rate 3661:Harcourt Brace Jovanovich 3286:electromagnetic radiation 3017:Applications and examples 2141:can be given in terms of 2134:{\displaystyle \tau _{c}} 1555:well-known expected value 3527: 2154:{\displaystyle \lambda } 1551:exponential distribution 567:{\displaystyle N(\tau )} 259:Measuring rates of decay 230:is the quantity at time 3495:approximations. In the 3365:for demonstrating that 3339:, and used in creating 3236:Newton's law of cooling 3088:(or, equivalently, the 2611:{\displaystyle T_{1/2}} 2510:{\displaystyle T_{1/2}} 1545:Exponential decay is a 1265:) as the corresponding 1119:constant of integration 1008:separation of variables 518:≈ 1.442695 half-lives. 88:transformation constant 80:disintegration constant 3467:route flapping damping 3182: 3139: 2977: 2724: 2612: 2565: 2538: 2511: 2473: 2381: 2358: 2271: 2155: 2135: 2108: 2078:multiplicative inverse 2064: 1932: 1905: 1861: 1716: 1536: 1487: 1370: 1295: 1206: 1108: 1057: 997: 930: 835: 808: 720: 697: 568: 539: 512: 463: 440: 371: 348: 309: 210: 139: 43: 3273:biological half-lives 3204:equivalent resistance 3183: 3140: 3065:first-order reactions 2978: 2725: 2613: 2566: 2564:{\displaystyle t_{2}} 2539: 2537:{\displaystyle t_{1}} 2512: 2474: 2382: 2380:{\displaystyle \tau } 2359: 2272: 2156: 2136: 2109: 2065: 1933: 1906: 1862: 1717: 1537: 1488: 1371: 1296: 1294:{\displaystyle \tau } 1255:differential operator 1207: 1109: 1066:Integrating, we have 1058: 998: 931: 836: 834:{\displaystyle \tau } 809: 721: 719:{\displaystyle \tau } 698: 569: 540: 538:{\displaystyle \tau } 513: 464: 462:{\displaystyle \tau } 441: 372: 370:{\displaystyle \tau } 349: 310: 308:{\displaystyle \tau } 211: 140: 60:differential equation 33: 3429:, has to maintain a 3229:If an object at one 3218:Atmospheric pressure 3149: 3145:so the half-life is 3116: 3055:of certain types of 3030:law of large numbers 2740: 2625: 2587: 2576:certain quantity is 2548: 2521: 2486: 2394: 2371: 2284: 2168: 2145: 2118: 2084: 1945: 1915: 1874: 1752: 1568: 1559:integration by parts 1503: 1496:or, on rearranging, 1394: 1327: 1285: 1128: 1073: 1017: 958: 848: 825: 737: 710: 621: 549: 529: 487: 453: 384: 361: 322: 299: 159: 97: 66:is the quantity and 3590:2002EJPh...23...21L 3511:Exponential formula 3410:Exponential backoff 3357:Arnd Leike, of the 2618:can be shown to be 1666: 1603: 1417: 1311:individual lifetime 3678:Simmons, George F. 3565:McGraw-Hill (2007) 3516:Exponential growth 3248:multi-exponential. 3178: 3135: 3057:chemical reactions 3047:Chemical reactions 2973: 2720: 2608: 2573:partial half-lives 2561: 2534: 2507: 2469: 2377: 2354: 2267: 2151: 2131: 2104: 2060: 1928: 1901: 1857: 1732:Branching fraction 1712: 1652: 1589: 1532: 1483: 1403: 1366: 1291: 1202: 1104: 1053: 993: 926: 831: 804: 716: 693: 564: 535: 508: 459: 436: 367: 344: 305: 206: 135: 44: 3647:978-0-07-144143-8 3521:Radioactive decay 3318:Thermoelectricity 3307:radioactive decay 3301:In a sample of a 3284:The intensity of 3092:) contained in a 2968: 2843: 2787: 2715: 2672: 2467: 2349: 2265: 2245: 2186: 2074:Partial mean life 1785: 1707: 1527: 1481: 1033: 979: 894: 667: 339: 118: 52:exponential decay 16:(Redirected from 3739: 3696: 3673: 3651: 3620: 3619: 3601: 3573: 3567: 3562: 3556: 3550: 3544: 3538: 3480: 3418:routing protocol 3404:Computer science 3392:glottochronology 3187: 3185: 3184: 3179: 3144: 3142: 3141: 3136: 3040:Natural sciences 3023:natural sciences 3004:Bateman equation 2997:pharmacokinetics 2982: 2980: 2979: 2974: 2969: 2967: 2963: 2962: 2953: 2952: 2934: 2933: 2924: 2923: 2905: 2904: 2895: 2894: 2881: 2880: 2879: 2870: 2869: 2860: 2859: 2849: 2844: 2842: 2841: 2840: 2828: 2827: 2815: 2814: 2804: 2793: 2788: 2786: 2785: 2776: 2765: 2760: 2759: 2755: 2729: 2727: 2726: 2721: 2716: 2714: 2713: 2712: 2700: 2699: 2689: 2678: 2673: 2671: 2670: 2661: 2650: 2645: 2644: 2640: 2617: 2615: 2614: 2609: 2607: 2606: 2602: 2570: 2568: 2567: 2562: 2560: 2559: 2543: 2541: 2540: 2535: 2533: 2532: 2516: 2514: 2513: 2508: 2506: 2505: 2501: 2478: 2476: 2475: 2470: 2468: 2466: 2465: 2464: 2452: 2451: 2441: 2440: 2439: 2430: 2429: 2419: 2414: 2413: 2409: 2386: 2384: 2383: 2378: 2363: 2361: 2360: 2355: 2350: 2348: 2347: 2346: 2334: 2333: 2323: 2322: 2321: 2312: 2311: 2301: 2296: 2295: 2276: 2274: 2273: 2268: 2266: 2264: 2263: 2251: 2246: 2244: 2243: 2231: 2226: 2225: 2213: 2212: 2200: 2199: 2187: 2185: 2184: 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2810: 2806: 2805: 2794: 2792: 2781: 2777: 2766: 2764: 2751: 2747: 2743: 2741: 2738: 2737: 2708: 2704: 2695: 2691: 2690: 2679: 2677: 2666: 2662: 2651: 2649: 2636: 2632: 2628: 2626: 2623: 2622: 2598: 2594: 2590: 2588: 2585: 2584: 2555: 2551: 2549: 2546: 2545: 2528: 2524: 2522: 2519: 2518: 2497: 2493: 2489: 2487: 2484: 2483: 2460: 2456: 2447: 2443: 2442: 2435: 2431: 2425: 2421: 2420: 2418: 2405: 2401: 2397: 2395: 2392: 2391: 2372: 2369: 2368: 2342: 2338: 2329: 2325: 2324: 2317: 2313: 2307: 2303: 2302: 2300: 2291: 2287: 2285: 2282: 2281: 2259: 2255: 2250: 2239: 2235: 2230: 2221: 2217: 2208: 2204: 2195: 2191: 2180: 2176: 2171: 2169: 2166: 2165: 2146: 2143: 2142: 2125: 2121: 2119: 2116: 2115: 2096: 2085: 2082: 2081: 2043: 2039: 2032: 2028: 2022: 2018: 2001: 1997: 1988: 1984: 1977: 1973: 1967: 1963: 1946: 1943: 1942: 1922: 1918: 1916: 1913: 1912: 1894: 1890: 1881: 1877: 1875: 1872: 1871: 1842: 1838: 1829: 1825: 1813: 1809: 1797: 1793: 1777: 1760: 1758: 1753: 1750: 1749: 1734: 1728: 1699: 1677: 1673: 1661: 1656: 1630: 1626: 1620: 1616: 1598: 1593: 1569: 1566: 1565: 1547:scalar multiple 1521: 1517: 1512: 1504: 1501: 1500: 1472: 1468: 1466: 1438: 1434: 1428: 1424: 1412: 1407: 1395: 1392: 1391: 1350: 1346: 1340: 1336: 1328: 1325: 1324: 1315:arithmetic mean 1286: 1283: 1282: 1275: 1236: 1221: 1189: 1185: 1179: 1175: 1160: 1156: 1150: 1146: 1129: 1126: 1125: 1117:where C is the 1074: 1071: 1070: 1022: 1020: 1018: 1015: 1014: 971: 963: 961: 959: 956: 955: 949: 913: 909: 905: 877: 867: 863: 859: 857: 849: 846: 845: 826: 823: 822: 789: 785: 781: 776: 769: 765: 759: 755: 738: 735: 734: 711: 708: 707: 647: 645: 632: 628: 624: 622: 619: 618: 613: 593: 587: 550: 547: 546: 530: 527: 526: 503: 494: 490: 488: 485: 484: 475: 471: 470: 454: 451: 450: 423: 416: 412: 406: 402: 385: 382: 381: 362: 359: 358: 331: 323: 320: 319: 300: 297: 296: 284:(or simply the 266: 261: 249: 241: 235: 231: 220: 191: 187: 181: 177: 160: 157: 156: 110: 102: 100: 98: 95: 94: 67: 63: 39: 35: 28: 23: 22: 15: 12: 11: 5: 3745: 3735: 3734: 3720: 3719: 3714: 3709: 3702: 3701:External links 3699: 3698: 3697: 3674: 3669: 3659:, Fort Worth: 3657:Modern Physics 3652: 3646: 3628: 3625: 3622: 3621: 3568: 3557: 3545: 3543:, p. 384) 3532: 3531: 3529: 3526: 3525: 3524: 3518: 3513: 3506: 3503: 3483: 3482: 3475: 3474: 3473: 3472: 3471: 3405: 3402: 3401: 3400: 3387: 3375: 3372: 3371: 3370: 3363:Ig Nobel Prize 3352: 3341:ADSR envelopes 3327: 3314: 3293: 3276: 3249: 3239: 3221: 3209: 3208: 3207: 3177: 3174: 3171: 3168: 3165: 3162: 3158: 3154: 3134: 3131: 3127: 3124: 3121: 3104:of resistance 3080:Electrostatics 3076: 3041: 3038: 3018: 3015: 2988: 2985: 2984: 2983: 2972: 2966: 2961: 2957: 2951: 2947: 2943: 2940: 2937: 2932: 2928: 2922: 2918: 2914: 2911: 2908: 2903: 2899: 2893: 2889: 2885: 2878: 2874: 2868: 2864: 2858: 2854: 2847: 2839: 2835: 2831: 2826: 2822: 2818: 2813: 2809: 2803: 2800: 2797: 2791: 2784: 2780: 2775: 2772: 2769: 2763: 2758: 2754: 2750: 2746: 2731: 2730: 2719: 2711: 2707: 2703: 2698: 2694: 2688: 2685: 2682: 2676: 2669: 2665: 2660: 2657: 2654: 2648: 2643: 2639: 2635: 2631: 2605: 2601: 2597: 2593: 2558: 2554: 2531: 2527: 2504: 2500: 2496: 2492: 2480: 2479: 2463: 2459: 2455: 2450: 2446: 2438: 2434: 2428: 2424: 2417: 2412: 2408: 2404: 2400: 2376: 2365: 2364: 2353: 2345: 2341: 2337: 2332: 2328: 2320: 2316: 2310: 2306: 2299: 2294: 2290: 2278: 2277: 2262: 2258: 2254: 2249: 2242: 2238: 2234: 2229: 2224: 2220: 2216: 2211: 2207: 2203: 2198: 2194: 2190: 2183: 2179: 2175: 2150: 2128: 2124: 2103: 2099: 2095: 2092: 2089: 2071: 2070: 2059: 2054: 2051: 2046: 2042: 2038: 2035: 2031: 2025: 2021: 2017: 2012: 2009: 2004: 2000: 1996: 1991: 1987: 1983: 1980: 1976: 1970: 1966: 1962: 1959: 1956: 1953: 1950: 1925: 1921: 1897: 1893: 1889: 1884: 1880: 1868: 1867: 1856: 1853: 1850: 1845: 1841: 1837: 1832: 1828: 1824: 1821: 1816: 1812: 1808: 1805: 1800: 1796: 1792: 1789: 1783: 1780: 1775: 1772: 1769: 1766: 1763: 1757: 1727: 1724: 1723: 1722: 1711: 1706: 1703: 1698: 1695: 1692: 1686: 1683: 1680: 1676: 1672: 1669: 1664: 1659: 1655: 1651: 1648: 1645: 1639: 1636: 1633: 1629: 1623: 1619: 1615: 1612: 1609: 1606: 1601: 1596: 1592: 1588: 1585: 1582: 1579: 1576: 1573: 1543: 1542: 1531: 1524: 1520: 1516: 1511: 1508: 1494: 1493: 1480: 1475: 1471: 1465: 1462: 1459: 1456: 1453: 1447: 1444: 1441: 1437: 1431: 1427: 1423: 1420: 1415: 1410: 1406: 1402: 1399: 1377: 1376: 1364: 1359: 1356: 1353: 1349: 1343: 1339: 1335: 1332: 1307:expected value 1290: 1274: 1271: 1234: 1219: 1213: 1212: 1198: 1195: 1192: 1188: 1182: 1178: 1174: 1169: 1166: 1163: 1159: 1153: 1149: 1145: 1142: 1139: 1136: 1133: 1115: 1114: 1102: 1099: 1096: 1093: 1090: 1087: 1084: 1081: 1078: 1064: 1063: 1052: 1049: 1046: 1043: 1040: 1037: 1032: 1028: 1025: 1004: 1003: 992: 989: 986: 983: 977: 974: 969: 966: 948: 945: 937: 936: 925: 920: 916: 912: 908: 904: 901: 898: 892: 889: 886: 883: 880: 874: 870: 866: 862: 856: 853: 830: 815: 814: 803: 796: 792: 788: 784: 779: 775: 772: 768: 762: 758: 754: 751: 748: 745: 742: 715: 704: 703: 692: 689: 686: 683: 680: 677: 674: 671: 666: 662: 659: 656: 653: 650: 644: 639: 635: 631: 627: 611: 589:Main article: 586: 583: 563: 560: 557: 554: 534: 506: 502: 497: 493: 458: 447: 446: 435: 430: 426: 422: 419: 415: 409: 405: 401: 398: 395: 392: 389: 366: 355: 354: 343: 338: 335: 330: 327: 304: 265: 262: 260: 257: 239: 217: 216: 205: 200: 197: 194: 190: 184: 180: 176: 173: 170: 167: 164: 146: 145: 134: 131: 128: 125: 122: 116: 113: 108: 105: 50:is subject to 26: 18:Decay constant 9: 6: 4: 3: 2: 3744: 3733: 3730: 3729: 3727: 3718: 3715: 3713: 3710: 3708: 3705: 3704: 3695: 3691: 3687: 3683: 3679: 3675: 3672: 3670:0-03-004844-3 3666: 3662: 3658: 3653: 3649: 3643: 3639: 3635: 3631: 3630: 3617: 3613: 3609: 3605: 3600: 3595: 3591: 3587: 3583: 3579: 3572: 3566: 3561: 3555:, p. 15) 3554: 3553:Simmons (1972 3549: 3542: 3537: 3533: 3522: 3519: 3517: 3514: 3512: 3509: 3508: 3498: 3494: 3490: 3485: 3479: 3468: 3464: 3460: 3456: 3452: 3448: 3444: 3443:not available 3440: 3436: 3432: 3431:routing table 3428: 3424: 3420: 3419: 3414: 3413: 3411: 3398: 3394: 3393: 3388: 3384: 3382: 3378: 3377: 3368: 3364: 3360: 3356: 3353: 3350: 3346: 3342: 3338: 3334: 3332: 3328: 3325: 3321: 3319: 3315: 3312: 3308: 3304: 3300: 3298: 3297:Radioactivity 3294: 3291: 3287: 3283: 3281: 3277: 3274: 3270: 3269: 3264: 3260: 3258: 3254: 3250: 3246: 3244: 3240: 3237: 3232: 3228: 3226: 3225:Heat transfer 3222: 3219: 3216: 3214: 3210: 3205: 3201: 3198: 3194: 3193: 3191: 3175: 3169: 3163: 3160: 3156: 3152: 3132: 3129: 3125: 3122: 3119: 3111: 3107: 3103: 3102:external load 3099: 3096:(capacitance 3095: 3091: 3087: 3083: 3081: 3077: 3074: 3070: 3066: 3062: 3058: 3054: 3050: 3048: 3044: 3043: 3037: 3035: 3031: 3026: 3024: 3014: 3012: 3007: 3005: 3000: 2998: 2994: 2970: 2959: 2955: 2949: 2945: 2938: 2930: 2926: 2920: 2916: 2909: 2901: 2897: 2891: 2887: 2876: 2872: 2866: 2862: 2856: 2852: 2845: 2837: 2833: 2829: 2824: 2820: 2816: 2811: 2807: 2801: 2798: 2795: 2789: 2782: 2778: 2773: 2770: 2767: 2761: 2756: 2752: 2748: 2744: 2736: 2735: 2734: 2717: 2709: 2705: 2701: 2696: 2692: 2686: 2683: 2680: 2674: 2667: 2663: 2658: 2655: 2652: 2646: 2641: 2637: 2633: 2629: 2621: 2620: 2619: 2603: 2599: 2595: 2591: 2581: 2579: 2574: 2571:are so-named 2556: 2552: 2529: 2525: 2502: 2498: 2494: 2490: 2461: 2457: 2453: 2448: 2444: 2436: 2432: 2426: 2422: 2415: 2410: 2406: 2402: 2398: 2390: 2389: 2388: 2374: 2351: 2343: 2339: 2335: 2330: 2326: 2318: 2314: 2308: 2304: 2297: 2292: 2288: 2280: 2279: 2260: 2256: 2252: 2247: 2240: 2236: 2232: 2227: 2222: 2218: 2214: 2209: 2205: 2201: 2196: 2192: 2188: 2181: 2177: 2173: 2164: 2163: 2162: 2148: 2126: 2122: 2114:. A combined 2101: 2097: 2093: 2090: 2087: 2079: 2075: 2057: 2052: 2044: 2040: 2033: 2029: 2023: 2019: 2015: 2010: 2002: 1998: 1994: 1989: 1985: 1978: 1974: 1968: 1964: 1960: 1954: 1948: 1941: 1940: 1939: 1923: 1919: 1895: 1891: 1887: 1882: 1878: 1854: 1851: 1843: 1839: 1835: 1830: 1826: 1819: 1814: 1810: 1806: 1803: 1798: 1794: 1790: 1787: 1781: 1778: 1770: 1764: 1761: 1755: 1748: 1747: 1746: 1744: 1740: 1733: 1709: 1704: 1701: 1696: 1693: 1690: 1684: 1681: 1678: 1674: 1670: 1667: 1657: 1653: 1649: 1646: 1643: 1637: 1634: 1631: 1627: 1621: 1617: 1613: 1610: 1607: 1604: 1594: 1590: 1586: 1580: 1574: 1571: 1564: 1563: 1562: 1560: 1556: 1552: 1548: 1529: 1522: 1518: 1514: 1509: 1506: 1499: 1498: 1497: 1478: 1473: 1469: 1463: 1460: 1457: 1454: 1451: 1445: 1442: 1439: 1435: 1429: 1425: 1421: 1418: 1408: 1404: 1400: 1397: 1390: 1389: 1388: 1386: 1382: 1362: 1357: 1354: 1351: 1347: 1341: 1337: 1333: 1330: 1323: 1322: 1321: 1318: 1316: 1312: 1308: 1304: 1288: 1280: 1279:mean lifetime 1270: 1268: 1267:eigenfunction 1264: 1260: 1256: 1252: 1248: 1242: 1240: 1233: 1229: 1225: 1218: 1196: 1193: 1190: 1186: 1180: 1176: 1172: 1167: 1164: 1161: 1157: 1151: 1147: 1143: 1137: 1131: 1124: 1123: 1122: 1120: 1100: 1097: 1094: 1091: 1088: 1085: 1082: 1079: 1076: 1069: 1068: 1067: 1050: 1047: 1044: 1041: 1038: 1035: 1030: 1026: 1023: 1013: 1012: 1011: 1009: 990: 987: 984: 981: 975: 972: 967: 964: 954: 953: 952: 944: 942: 939:For example, 923: 918: 914: 910: 906: 902: 899: 896: 887: 881: 878: 872: 868: 864: 860: 854: 851: 844: 843: 842: 828: 819: 801: 794: 790: 786: 782: 777: 773: 770: 766: 760: 756: 752: 746: 740: 733: 732: 731: 729: 713: 690: 684: 678: 675: 672: 669: 664: 657: 651: 648: 642: 637: 633: 629: 625: 617: 616: 615: 610: 606: 602: 598: 592: 582: 580: 575: 558: 552: 532: 524: 519: 504: 500: 495: 491: 480: 479: 456: 433: 428: 424: 420: 417: 413: 407: 403: 399: 393: 387: 380: 379: 378: 364: 341: 336: 333: 328: 325: 318: 317: 316: 302: 294: 293: 292:time constant 288:), where the 287: 283: 282:mean lifetime 279: 275: 271: 264:Mean lifetime 256: 252: 245: 238: 227: 223: 203: 198: 195: 192: 188: 182: 178: 174: 168: 162: 155: 154: 153: 151: 132: 129: 126: 123: 120: 114: 111: 106: 103: 93: 92: 91: 89: 85: 84:rate constant 81: 77: 73: 61: 57: 53: 49: 32: 19: 3732:Exponentials 3684:, New York: 3681: 3656: 3633: 3584:(1): 21–26. 3581: 3577: 3571: 3560: 3548: 3536: 3492: 3488: 3466: 3454: 3446: 3442: 3438: 3416: 3396: 3390: 3379: 3354: 3345:synthesizers 3329: 3316: 3303:radionuclide 3295: 3290:Beer-Lambert 3278: 3266: 3253:Pharmacology 3251: 3243:Luminescence 3241: 3223: 3211: 3110:mirror image 3105: 3097: 3078: 3045: 3027: 3020: 3008: 3001: 2990: 2732: 2582: 2572: 2481: 2366: 2073: 2072: 1869: 1742: 1738: 1735: 1544: 1495: 1380: 1378: 1319: 1310: 1302: 1278: 1276: 1262: 1258: 1243: 1238: 1231: 1227: 1223: 1216: 1214: 1121:, and hence 1116: 1065: 1005: 950: 941:polonium-210 938: 820: 816: 705: 608: 604: 600: 596: 594: 578: 576: 522: 520: 477: 448: 356: 290:exponential 289: 285: 281: 273: 269: 267: 250: 243: 236: 225: 221: 218: 147: 87: 83: 79: 75: 56:proportional 51: 45: 42:from 0 to 5. 3686:McGraw-Hill 3638:McGraw-Hill 3497:SVG version 3449:), the BGP 3355:Beer froth: 3263:metabolized 3231:temperature 152:below) is: 3627:References 3447:vice versa 3408:See also: 3389:In simple 3349:overdamped 3331:Vibrations 3324:Thermistor 3311:radiogenic 3257:toxicology 3213:Geophysics 3011:formulated 1730:See also: 1379:first let 1247:eigenvalue 574:, is 368. 150:derivation 3616:250873501 3594:CiteSeerX 3439:available 3415:The core 3361:, won an 3268:clearance 3200:resistors 3164:⁡ 3120:τ 3094:capacitor 3090:potential 3073:catalyzed 2834:λ 2821:λ 2808:λ 2799:⁡ 2779:λ 2771:⁡ 2706:λ 2693:λ 2684:⁡ 2664:λ 2656:⁡ 2375:τ 2340:τ 2327:τ 2315:τ 2305:τ 2289:τ 2257:τ 2237:τ 2219:λ 2206:λ 2193:λ 2178:τ 2149:λ 2123:τ 2102:λ 2088:τ 2041:λ 2034:− 1999:λ 1986:λ 1979:− 1920:λ 1892:λ 1879:λ 1840:λ 1827:λ 1811:λ 1795:λ 1756:− 1705:λ 1682:λ 1679:− 1668:λ 1663:∞ 1654:∫ 1635:λ 1632:− 1614:⋅ 1608:⋅ 1600:∞ 1591:∫ 1584:⟩ 1578:⟨ 1572:τ 1515:λ 1479:λ 1464:⋅ 1443:λ 1440:− 1422:⋅ 1414:∞ 1405:∫ 1355:λ 1352:− 1305:) is the 1289:τ 1194:λ 1191:− 1165:λ 1162:− 1092:λ 1089:− 1080:⁡ 1042:λ 1039:− 988:λ 985:− 903:⋅ 897:≈ 882:⁡ 852:τ 829:τ 771:− 728:ln 2 714:τ 679:⁡ 673:τ 665:λ 652:⁡ 605:half-life 591:Half-life 585:Half-life 559:τ 533:τ 501:⁡ 457:τ 449:and that 429:τ 418:− 365:τ 337:λ 326:τ 303:τ 196:λ 193:− 127:λ 124:− 3726:Category 3694:75173716 3680:(1972), 3640:. 2007. 3505:See also 3423:Internet 3313:nuclide. 3197:parallel 3190:the dual 3061:reactant 1303:lifetime 1251:negative 1230:= 0, as 286:lifetime 62:, where 48:quantity 3586:Bibcode 3491:and 72/ 3421:on the 3381:Finance 1549:of the 1253:of the 474:⁄ 3692:  3667:  3644:  3614:  3596:  3470:route. 3451:router 3435:packet 3347:. An 3069:enzyme 2578:halved 2482:where 900:1.4427 219:where 72:lambda 3612:S2CID 3528:Notes 3455:flaps 3445:(and 3386:fund. 3265:(see 3234:also 3053:rates 1257:with 1241:= 0. 86:, or 3690:LCCN 3665:ISBN 3642:ISBN 3461:and 3367:beer 3292:law. 3255:and 3084:The 3051:The 2995:and 2544:and 3604:doi 3463:RAM 3459:CPU 3441:to 3427:BGP 3397:two 3343:in 3006:. 2991:In 2161:s: 1743:sum 1010:), 612:1/2 492:log 278:set 253:= 0 246:(0) 3728:: 3688:, 3663:, 3610:. 3602:. 3592:. 3582:23 3580:. 3425:, 3161:ln 3036:. 3025:. 2796:ln 2768:ln 2681:ln 2653:ln 2580:. 1938:. 1561:. 1387:: 1281:, 1222:= 1077:ln 879:ln 676:ln 649:ln 545:, 295:, 255:. 242:= 234:, 90:: 82:, 78:, 46:A 3650:. 3618:. 3606:: 3588:: 3493:t 3489:t 3383:: 3333:: 3320:: 3299:: 3282:: 3259:: 3245:: 3238:. 3227:: 3215:: 3176:. 3173:) 3170:2 3167:( 3157:C 3153:R 3133:, 3130:C 3126:R 3123:= 3106:R 3098:C 3082:: 3071:- 3049:: 2971:. 2965:) 2960:3 2956:t 2950:2 2946:t 2942:( 2939:+ 2936:) 2931:3 2927:t 2921:1 2917:t 2913:( 2910:+ 2907:) 2902:2 2898:t 2892:1 2888:t 2884:( 2877:3 2873:t 2867:2 2863:t 2857:1 2853:t 2846:= 2838:3 2830:+ 2825:2 2817:+ 2812:1 2802:2 2790:= 2783:c 2774:2 2762:= 2757:2 2753:/ 2749:1 2745:T 2718:. 2710:2 2702:+ 2697:1 2687:2 2675:= 2668:c 2659:2 2647:= 2642:2 2638:/ 2634:1 2630:T 2604:2 2600:/ 2596:1 2592:T 2557:2 2553:t 2530:1 2526:t 2503:2 2499:/ 2495:1 2491:T 2462:2 2458:t 2454:+ 2449:1 2445:t 2437:2 2433:t 2427:1 2423:t 2416:= 2411:2 2407:/ 2403:1 2399:T 2352:. 2344:2 2336:+ 2331:1 2319:2 2309:1 2298:= 2293:c 2261:2 2253:1 2248:+ 2241:1 2233:1 2228:= 2223:2 2215:+ 2210:1 2202:= 2197:c 2189:= 2182:c 2174:1 2127:c 2098:/ 2094:1 2091:= 2058:. 2053:t 2050:) 2045:c 2037:( 2030:e 2024:0 2020:N 2016:= 2011:t 2008:) 2003:2 1995:+ 1990:1 1982:( 1975:e 1969:0 1965:N 1961:= 1958:) 1955:t 1952:( 1949:N 1924:c 1896:2 1888:+ 1883:1 1855:. 1852:N 1849:) 1844:2 1836:+ 1831:1 1823:( 1820:= 1815:2 1807:N 1804:+ 1799:1 1791:N 1788:= 1782:t 1779:d 1774:) 1771:t 1768:( 1765:N 1762:d 1739:N 1710:. 1702:1 1697:= 1694:t 1691:d 1685:t 1675:e 1671:t 1658:0 1650:= 1647:t 1644:d 1638:t 1628:e 1622:0 1618:N 1611:c 1605:t 1595:0 1587:= 1581:t 1575:= 1530:. 1523:0 1519:N 1510:= 1507:c 1474:0 1470:N 1461:c 1458:= 1455:t 1452:d 1446:t 1436:e 1430:0 1426:N 1419:c 1409:0 1401:= 1398:1 1381:c 1363:, 1358:t 1348:e 1342:0 1338:N 1334:= 1331:N 1263:t 1261:( 1259:N 1239:t 1235:0 1232:N 1228:t 1224:e 1220:0 1217:N 1197:t 1187:e 1181:0 1177:N 1173:= 1168:t 1158:e 1152:C 1148:e 1144:= 1141:) 1138:t 1135:( 1132:N 1101:C 1098:+ 1095:t 1086:= 1083:N 1051:. 1048:t 1045:d 1036:= 1031:N 1027:N 1024:d 991:N 982:= 976:t 973:d 968:N 965:d 924:. 919:2 915:/ 911:1 907:t 891:) 888:2 885:( 873:2 869:/ 865:1 861:t 855:= 802:. 795:2 791:/ 787:1 783:t 778:/ 774:t 767:2 761:0 757:N 753:= 750:) 747:t 744:( 741:N 691:. 688:) 685:2 682:( 670:= 661:) 658:2 655:( 643:= 638:2 634:/ 630:1 626:t 609:t 601:t 599:( 597:N 579:e 562:) 556:( 553:N 523:N 505:e 496:2 478:e 472:1 434:, 425:/ 421:t 414:e 408:0 404:N 400:= 397:) 394:t 391:( 388:N 342:. 334:1 329:= 274:t 272:( 270:N 251:t 244:N 240:0 237:N 232:t 228:) 226:t 224:( 222:N 204:, 199:t 189:e 183:0 179:N 175:= 172:) 169:t 166:( 163:N 133:. 130:N 121:= 115:t 112:d 107:N 104:d 70:( 68:λ 64:N 40:x 36:λ 20:)

Index

Decay constant

quantity
proportional
differential equation
lambda
derivation
set
time constant
e
Half-life
ln 2
polonium-210
separation of variables
constant of integration
eigenvalue
negative
differential operator
eigenfunction
expected value
arithmetic mean
probability density function
scalar multiple
exponential distribution
well-known expected value
integration by parts
Branching fraction
multiplicative inverse
halved
nuclear science

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