Master Isotope Table — NIST SRD-128 Kα₁ (Z =

Z	Elem	Known	Stable	Unstable	Pred.	Gap	Nuclear γ (keV)	NIST Kα₁ (keV)	Context
81	Tl	39	2	37	93	54	2614.5	72.871	²⁰⁸Tl (Th-series) + XRF
82	Pb	43	4	39	102	59	351.9 / 46.5	74.969	²¹⁴Pb, ²¹⁰Pb γ + XRF
83	Bi	41	0	41	97	56	609.3 / 1120.3 / 1764.5	77.107	²¹⁴Bi γ + XRF
84	Po	42	0	42	100	58	—	79.292	α-emitter; XRF line
85	At	39	0	39	93	54	—	81.580	Short-lived α, tracer
86	Rn	39	0	39	93	54	609.3 / 1764.5	83.900	γs from daughters; noble gas
87	Fr	34	0	34	81	47	—	86.300	No stable isotopes; XRF line
88	Ra	34	0	34	81	47	186.2	88.800	²²⁶Ra tracer + XRF
89	Ac	33	0	33	78	45	911.2	91.400	²²⁸Ac γ emitter + XRF
90	Th	31	1	30	74	43	238.6 / 2614.5	94.000	Th-series γs + XRF
91	Pa	29	0	29	69	40	312.0	96.700	²³³Pa intermediate + XRF
92	U	28	0	28	66	38	1001.0	98.439	²³⁴mPa γ (U-series) + XRF
93	Np	20	0	20	47	27	106.1	—	Synthetic; γ emitter
94	Pu	20	0	20	47	27	375.0 / 51.6	—	²³⁹Pu, ²⁴¹Pu γ lines
95	Am	17	0	17	40	23	59.5	—	²⁴¹Am smoke detectors
96	Cm	19	0	19	45	26	333.0	—	²⁴⁴Cm neutron source
97	Bk	21	0	21	50	29	—	—	Synthetic; tracer
98	Cf	20	0	20	47	27	—	—	²⁵²Cf neutron source
99	Es	18	0	18	42	24	—	—	Synthetic; short-lived
100	Fm	19	0	19	45	26	—	—	Synthetic; ²⁵⁷Fm longest-lived

Key terms in plain language

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Broadband

A general term for always-on, high-speed Internet access. Broadband can be delivered over fiber, cable, DSL, fixed wireless, cellular, or satellite networks.

Cloud Computing

Computing resources—such as applications, servers, storage, or databases—delivered from remote infrastructure and scaled as requirements change.

Cybersecurity

The practices and controls used to protect identities, devices, networks, applications, and data from unauthorized access, disruption, or manipulation.

Identity and Access Management (IAM)

The systems and policies that determine who a user is, what resources they may access, and how that access is authenticated and reviewed.

API

An application programming interface is a defined way for software systems to exchange data or request functions from one another.

Artificial Intelligence (AI)

Software designed to perform tasks involving prediction, classification, generation, reasoning, or decision support. Business use still requires clear data, governance, security, and human accountability.